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You want, or need, to communicate from beyond cell signal. We test the products and services and report back, on equipment from Motorola, Garmin, SPOT, ACR, Zoleo, and more.
2024 line up of some tested messengers. Left to right, top to bottom: Zoleo, inReach Mini, Messenger, Messenger Plus, GPSMAP, PLB 1, SpotX, BivyStick, Spot Gen4, Somewear Labs.
We took the 13 satellite messengers into the backcountry and assessed their emergency and non-emergency functions, signal coverage, and ease of use. We used them for hundreds of hours and then compared how the subscription plans compare.
The best messenger is the Garmin inReach Messenger Plus. It has nearly flawless emergency and non-emergency messaging capabilities and lets you send photos and short voice memos. If you want to save $200 and don't need to send photos, the Garmin inReach Messenger is the best value.
Many handheld GPS devices also have messaging abilities. In addition, some recent releases in our walkie talkies have incredible range and may complement some satellite messenger applications.
Editor's Note: On November 20, 2024, we added the inReach Messenger Plus and commentary on the newly enabled non-emergency messaging capability of the iPhone.
Exposed "1-move" SOS button, unproven satellite network
No on-device message viewing or composition, USB-C charging (could be a pro for some)
Not the absolute lightest, tiny screen, button use
Small antenna, small screen
Expensive initial purchase, slightly heavier and bulkier than some others
No non-emergency messaging
Limited functionality, limited coverage, not a huge upgrade from previous version
Only supports SOS and tracking on the device itself, no custom messaging, occasional hardware issues
Must aim the phone to send and receive messages, limited satellite coverage, further reliance on smartphone
Larger and heavier than closest competitor
No on-device message viewing or composition, heavier than close competitors
Bulky, tough customer and tech service
Bulky and heavy, expensive
Bottom Line
An innovative, compact, non-standard entry to this category of equipment. The exposed SOS button is a deal breaker; it seems way too vulnerable to inadvertent emergency triggering
A small, light, and full-function two-way messenger that competes closely with the top of the heap
For how most people actually use their satellite communicators, this is one of the best products on the market
The best two-way texting satellite device on the market, now with better battery life and interface
This top of the line satellite messenger from the category's most recognized brand raises the bar for what we expect of satellite communications in the wild
This device provides a compact and affordable “help me” button in your pocket
This lower-cost option is good for occasional, one-way communication or for tracking of very long single-push efforts where one needs documentation
Compact, simple, two-way satellite communications using proven technology and relatively affordable subscription options
Casual outdoor enthusiasts (or even those that occasionally find themselves in an emergency without cell signal) now have access to satellite communications - with caveats
An excellent emergency-only (with one debatable caveat) personal beacon for wilderness safety
This nearly perfect device provides comprehensive, polished, two-way satellite communications at a fair price
A two-way texting device with a built-in keyboard reminiscent of old Blackberry phones with slightly limited geographic coverage
If you want full handheld GPS functionality with your satellite communications, this is the product and service for you
The Garmin inReach Messenger Plus is the best device for thorough wilderness communications. It is as reliable as satellite communications can get. It is compact enough to carry on any human-powered adventure. It leverages proven and established partnerships, protocols, and technologies. Finally, it includes all the latest and greatest messaging attributes. The accepted bare minimum in satellite messaging is two-way texting and SOS messaging. The Messenger Plus has that. You should expect seamless messaging from cellular/WiFi and app-based text composition and viewing. The Plus has that too. Finally, we haven't expected photo and voice transmission on a device like this for years. Garmin accelerated the timeline for Messenger Plus. This device and service offer the transmission of photos and short voice memos.
Multiple other devices and services offer the basic messaging function that we reference. However, only the Garmin inReach Messenger Plus offers photo and voice memo transmission. The only downside of the added features of the Messenger Plus is the cost. If using your device infrequently, you may save money going with the ACR Bivy Stick.
If you don't need to send photos and voice memos, the Garmin inReach Messenger saves you a few hundred dollars over the Messenger Plus. Both devices have the same form factor and use the same satellite network and dispatch services. They share subscription rates and options. They both offer a rudimentary on-device interface and access to a much more useful smartphone app. Both offer long battery life and the option to charge small electronics from the internal inReach battery.
The only potential advantage of Messenger vs. Messenger Plus is better battery life. At maximum battery economy, they aren't that different. inReach claims 28 days for the Messenger and 25 days for the Messenger Plus. However, this isn't a direct comparison. To get 25 days of battery life on Messenger Plus, you must use a low battery mode, and the device will only check for incoming messages for 10 minutes after sending them and then once every hour. The claimed 28 days (we haven't achieved claimed battery life in our testing, but we've come close enough to use Garmin's numbers for effective internal comparison) in the Messenger-sans-Plus is achievable with continuous message checks. There is no battery savings option on Messenger Plus. To get continuous message monitoring on Messenger Plus, you will burn through the battery in about 5 days. Our testing verifies this: low power mode in the Messenger Plus seems to have about the same battery drain rate as the Messenger. Higher power mode in the Messenger Plus visibly drains the battery faster. Either way, though, these devices have excellent battery life for those with good backcountry battery habits.
Garmin's refined inReach Messenger is a legitimate upgrade from their other offerings. It isn't perfect, but advancements do seem to be plateauing after a heady few recent years.
While the ACR Bivy Stick does not have the same messaging convenience as the Garmin models, it is still quite capable. The flexible activation and ever-more-competitive pricing may make it the best value for your intended use.
At the time of testing, if you activate it once a year, the ACR Bivy Stick has one of the lowest 5-year “cost of ownership” measures for global coverage and two-way messaging. Since many will use their wilderness communication device that way, it earns an award among the other value options. If in-device two-way messaging isn't a priority, the Zoleo is another affordable option — know that you need your smartphone and the Zoleo app to compose messages.
If custom messaging is not important to you and you're only looking for an emergency signaling device, the Ocean Signal rescueME PLB1 is your best option. It is expensive upfront, but no annual fees or subscription plans are required. It broadcasts a distress signal through two radio channels, 406 MHz and 121.5 MHz. They are sent to a monitored satellite network and a local aircraft distress frequency. This powerful transmission is sent on the military's reliable COSPAS-SARSAT network.
Unfortunately, this personal locator beacon does not confirm in any way that someone has received your distress signal. The PLB1 is an excellent option for pure, personal locator beacon SOS functions and offers a solid value. Still, the two-way messaging of many other options makes them more useful products overall. If you want more messaging functionality, check out the SPOT X, which has a keyboard on the device.
The SPOT X fills a small niche. This two-way, satellite-linked, backcountry messaging device works entirely on its own. The built-in physical QWERTY keyboard distinguishes it from all of its competitors. This keyboard allows users to text readily without linking to a separate, battery-draining device. It can be linked to a smartphone if you prefer a smartphone interface or want that option.
The SPOT X is unique, but it is exceeded in some ways by its close competitors, particularly regarding size and satellite system used. Additionally, we had part of the first (of two) SPOT X antennae we tested come apart. Functionality did not change with this issue, but it's not encouraging. These drawbacks are not at all deal breakers. If that physical keyboard and its benefits appeal to you, there is no reason not to choose the SPOT X. If you don't mind spending a bit more, our favorites are the Garmin inReach Messenger and Garmin inReach Mini 2.
The full keyboard of the SPOT X allows you to easily send and receive messages right on the device.
Credit: Jediah Porter
Compare Products
In all types of wilderness travel, effective communication is key. The products we review here all have their purpose, but some are definitely better suited for you than others. Shop carefully.
Credit: Jediah Porter
Why Trust GearLab
To compile this review, we carefully selected the top models of satellite messenger and personal locator beacons. It's usually impossible for us to test every product on the market satisfactorily for a particular category. With PLBs and satellite messengers, though, there aren't many options available, and we can test nearly every device. We've worked to get every new option, especially in the two-way satellite messaging device sub-category and from the list of devices small enough to carry on extended human-powered outings. The result is a set of tested products that represent all available satellite communication options currently on the market. From there, we purchased and activated these beacons and tested them for hundreds of hours in several distinct situations and locations. We do so while calling on decades of experience with wilderness communications. Test settings have varied through most latitudes, terrains, and climate/vegetation types.
We independently verify specs whenever it is practical to do so.
Credit: Jediah Porter
We augmented field tests with consultation and lab tests. We paid special attention to how well the devices did things most important in the function of a messenger/beacon, like message transmission, signal coverage, and ease of use. We also consulted with SAR experts and engineers who were familiar with the underlying technology. If you're looking for a comprehensive resource to help you find the device that will work best for you, you've come to the right place.
We tested personal locator beacons using a comprehensive testing plan comprised of five performance metrics:
SOS/Emergency Messaging (30% of overall score weighting)
Non-Emergency Messaging (25% weighting)
Signal Coverage (20% weighting)
Ease of Use (15% weighting)
Portability (10% weighting)
Mountain guide Jediah Porter heads up our personal locater beacon review. Aside from testing gear, Jed's primary work is mountain guiding, including rock, ice, alpine, and ski mountaineering trips. Jed guides full-time all around the world. In each of the few most recent years, he has racked up over 500,000 vertical feet of human-powered ascent. In 2020, he ascended 800,000 vertical feet of human-powered mountain terrain, mainly while backcountry skiing. Aside from climbing and skiing, you can find him dabbling in mountain biking, canoeing, hunting, fishing, trail running, and other adventure travel. His latest adventure is in parenting; he and his toddler daughter have logged dozens of nights deep in the backcountry through each of her first three years. He almost always brings a satellite messenger or personal locator beacon along on his adventures, something all his family appreciates. Jed brings professionalism, competence, and experience to test these important safety devices. Before taking over this category, he consulted for one of the major satellite communication network and hardware providers for a few years.
Composing a message on the device itself is a slow, laborious, one-letter-at-a-time procedure. But, it can be done and that is more than can be said of the inReach competitors.
These guys are staying in touch with an inReach in their pack connected to their phone. The phone provides interface clarity that the device doesn't need to integrate. Essentially, your ubiquitous smartphone serves as the "screen" for the smaller device.
The SPOT X ready to search for a signal.
Analysis and Test Results
It has become increasingly common for wilderness travelers to carry and use satellite communications. You might choose to buck that convention, but your loved ones hope you are at least considering such technology and service. We head to the wild to escape certain types of communication but are also vulnerable to spotty or nonexistent communication options. Strike your balance, and use our review findings to choose.
We mix and match some terminology herein—first, we reiterate what unites this review category. We aim to examine every satellite communication product small enough to carry on terrestrial, human-powered outdoor adventures. A subset of those examined receive full reviews. What we test here is described elsewhere as “PLBs,” "Satellite Messengers," and “Satellite SOS.” PLB stands for “Personal Locator Beacon.” This term is largely confined to the dedicated devices that send just emergency location information, like the OceanSignal PLB1 and the ACR ResQLink. Any devices that send (and maybe receive) non-emergency messages are called Satellite Messengers. “Satellite SOS” is a function or mode on any of these dedicated devices or, increasingly, built into other personal electronics, as in the newest iPhones.
What's the Best Value?
Note that the initial purchase price is only part of your decision. Some devices may require a much higher upfront cost, but when counting the cost of activation and subscription plans, they are closer- or even cheaper- over the long haul.
The best value for SOS/Emergency use is a device on the public-sector/governmental COSPAS-SARSAT network. The ACR devices are two examples. The rescueME PLB1 deserves a nod for its tiny size and access to the proven and free international satellite SAR network.
Summary of approximate costs of satellite messengers. It is quite hard to compare. But we try. Let this narrow down your choices, but then do your own homework too, so as to better price your actual use case.
Credit: Jediah Porter
Start-up offerings from Bivy Stick, ZOLEO, and Somewear Global Hotspot further increased the subscription options. All of these have low- to no-commitment subscription plans that are equal to or better than those offered by the established competitors. The bigger, older “legacy” contenders are responding with their own flexible, low-commitment subscription options. Finally, bigger, mainstream electronics companies (Apple and Motorola, to name two) are getting into the satellite communications game and offering their twists on the subscription/pricing matrix.
Suppose you will own and carry an iPhone anyway. In that case, the latest version now offers (in the USA and Canada, below 62 degrees latitude) their iPhone Satellite Messaging. This service, for now, is free for two years, and the hardware is automatically integrated into Apple iPhone 14 and newer models. You can also perform very basic non-emergency messaging with newer Apple iPhones. If you own the phone, this could be considered a “budget” choice.
Some newer Android phones also offer emergency messaging. However, as of November 2024, they do not offer the non-emergency messaging that the newer iPhones offer.
Current line up of compact, two way satellite messengers in our test. These are what most will be considering.
Credit: Jediah Porter
How Does Starlink Compare?
The $600 Starlink Mini has a $50-a-month Roam plan you can activate or deactivate anytime. This is the best value for using a laptop or smartphone in remote locations. The download speeds of 100+ Mbps are as fast (or faster) as many Americans' speeds in their home. However, the Mini weighs 7 lbs, and you need to carry a battery and a portable solar charger to power it, which is at least another 3 lbs. It is amazing how much value and capability you get in that package, but it is still 10+ lbs, which most people do not want to carry into the backcountry, especially on a day trip. Starlink Mini may make sense for your base camp if you have a bigger group that can split up the components and you are camping for a long time. Otherwise, the devices in this review are ideal for the average backcountry user and give you the ability to always have a lightweight device on you in an emergency.
SOS/Emergency Messaging
For many, sending an emergency signal is the primary reason for carrying a communication device into the wilderness. It's also the metric that unites the category. With varying degrees of effectiveness, these devices can summon help in a life or limb emergency. Some of them do not do anything more. SAR experts confirm that the most important information to relate is 1) where you are and 2) how bad it is. When you push the SOS button on any reviewed personal locator beacons, you send your GPS coordinates and say, “This is really, really bad.” There was a time, not long ago, when COSPAS-SARSAT-style devices did not include GPS data. The location was ascertained in a two-stage triangulation via the communication satellite and SAR aircraft. The uncertainty in a simple “help” notification implies the gravity of the situation. With satellite SOS transmission, you say, “Get here as fast as possible.”
The SOS button on the SPOT Gen4. It is covered with the orange flap to avoid accidental deployment. Don't let an inadvertent SOS message get out: it's dramatic, to put it mildly.
Credit: Jediah Porter
IMPORTANT: How Long Do Rescues Take?
The communication process, from activating your personal locator beacon's SOS function to notifying local Search and Rescue (SAR) resources, can take minutes to a maximum of a couple of hours. Depending on your location, on-the-ground SAR response time can vary from hours to weeks, regardless of the technology used to summon help. Response time following notification depends on terrain, weather, potential concurrent emergencies, not to mention local fiscal, personnel, and political factors. Educate yourself on the SAR resources where you choose to recreate. All the satellite-linked (and cellular, communication systems are similar enough in speed that they are essentially equal. Local response resources and conditions make your emergency resolution time vary the most.
Effective SOS messaging (read: help is summoned, acquired, and is helpful) requires a few steps and connects a few players. Let us spell out how it works and how different categories of devices accomplish these steps.
First, you need to have a device, current registration, a clear view of the sky, and the money and mobility to activate the SOS feature of your device. Don't take these things for granted. Finding yourself in an emergency is possible without one or more of these essential things in your favor. (A recent test-team visit to the dense forests of the Northeast US pointed out just how tenuous satellite signal can be. We went days at a time without reliable satellite coverage in the otherwise “benign” and compact wilderness of the “civilized” East Coast). The wilderness is dangerous. No piece of equipment will eliminate that danger. For an effective response, your emergency needs to be one that still gives you some time. Satellite communications can be nearly instant, but wilderness emergency response will take hours or days in even the most accessible wild spaces.
A wilderness emergency is no place to begin thinking about emergencies. This knee injury eventually required ACL reconstruction surgery. Leaving the field was a smooth process, thanks to careful advance planning and good communications.
Credit: Jediah Porter
Provided your emergency fits the above criteria, your device sends a signal to one of four satellite networks. We review equipment from six different brands, but they all use one of these four satellite networks. Once your distress signal reaches its satellite network, it must get to a staffed, terrestrial dispatch service. Only six operations provide all monitoring and dispatch services across the 12 devices from the seven brands we tested here. The staff at those services will identify your location and then work to secure local assistance for you. Your message will be methodically funneled to local resources. It is likely that, regardless of how your message goes out and is dispatched, the local SAR response will be the same. This final, crucial, local response depends on too many factors to list here. Do your homework to know your SAR options for any adventure.
Emergency response summoned from your satellite device is a function of the device and its service, plus a significant amount of variability in local resources. In fact, local SAR resources impact the outcome way more than the technology employed to summon that help.
Credit: Jediah Porter
SOS messaging says, “I am here and in dire need of assistance.” This is all that SAR needs to know in the worst of emergencies. Of course, being able to relate more nuanced information and answer questions from SAR responders is of great value. Satellite messengers or personal locator beacons that allow two-way, customized communication improve emergency response.
Both SPOT devices, all four Garmin devices, the Somewear Global Hotspot, ZOLEO, Motorola Defy, and the Bivy Stick use private networks and emergency dispatch systems. Aside from coverage differences, elaborated below, they work the same for SOS messaging. Of these, only the SPOT Gen4 doesn't allow two-way messaging in any context. With the rest of the aforementioned private sector devices and services, you can text the team back and forth to coordinate your emergency response.
In summary, the Garmin devices, Motorola, ZOLEO, Global Hotspot, Bivy Stick, and SPOT X are the best for emergency messaging since they offer the opportunity to send and receive more nuanced information in an emergency. For “send help now” signaling and nothing more, the Ocean Signal rescueME, ResQLink View, and SPOT Gen4 are nearly indistinguishable and have long been proven to work. Apple's iPhone Emergency Satellite SOS functionality, as long as you are within the coverage area (USA and Canada, for now, and ever-expanding, theoretically), works more like the two-way devices in that it allows for sharing of more nuanced information about your emergency.
There are two major types of emergency messaging networks used by devices in our review.
Public — The COSPAS-SARSAT satellite network is a product of international government cooperation. Tax dollars fund it, and it is free to use. It has provided satellite SAR support for more than 30 years. This network covers the entire planet and, with rare exceptions, is for emergency use only.
Private — These are for-profit services and partnerships operated by corporations or corporations. One example is Globalstar, the network that supports SPOT devices and the iPhone service. It currently does not cover the entire world. Be sure to research the Globalstar and SPOT coverage map to make sure it will work where you wish to adventure. Another example is Iridium, which supports the Garmin inReach, ZOLEO, Somewear, and Bivy Stick. It covers the entire planet, and its track record over the past decade or so has been less imperfect than that of Globalstar's. The Iridium-supported devices we tested worked more reliably than the Globalstar-supported devices. Iridium and Globalstar-enabled services partner with an external monitoring and dispatch service.
The “alphabet soup” that describes SOS messaging can be complicated. It doesn't help that many products overlap in the services they work with. Hopefully this diagram can shed some light.
Should You Navigate With Your Satellite Messenger?
The devices we test here are meant, first and foremost, to communicate with the outside world. In an emergency, the most critical information you can send with an SOS message is where you are. Most of the devices we tested feature a built-in GPS antenna that provides that location information, usually automatically. Once the hardware is there, it is simple for manufacturers to add software that leverages this GPS information for more routine navigation.
Some of the devices we review have navigation features. However, the fact is that these navigation features are afterthoughts, and they drain the battery of a potentially vital piece of communication equipment.
Modern smartphone apps work so much better for navigation than your satellite messenger. We strongly recommend using a smartphone as your primary navigation mode. Because of that, we downplay (basically ignore) the navigational attributes of the satellite messengers we have assessed. If you plan to do any navigation with your wilderness communication device, your only reasonable option, due to its extended battery life, is the Garmin GPSMAP 66i.
If you navigate with your satellite device (or any device, for that matter), note that some important terminology matters. Many people, ourselves included, inaccurately use “GPS” as a synonym for “GNSS.” GNSS is the proper, generic abbreviation for Global Navigation Satellite System. “GPS,” for “Global Positioning System,” is just one currently available GNSS. Devices are increasingly using different GNSSs. More GNSS options in a single device increase the resolution of location data. That increased resolution is more important in urban and highway navigation than it is in outdoor recreation.
The Zoleo satellite device on a Teton ski tour. Zoleo recently added tracking functionality to the service. Certain types of users in certain situations will appreciate this.
Credit: Jediah Porter
Non-Emergency Messaging
Regarding non-emergency messaging, there are various options available on these devices. Some have features that allow you to text and share your location, giving you the feel of using a smartphone. Others have a more straightforward approach, offering the ability to send a quick message saying that you're okay and where you are. Then, some have no non-emergency messaging options at all. Different devices offer different levels of performance and features. Additionally, some devices come equipped with location tracking capabilities, which can be set to share your location and status update automatically at regular intervals. Finally, one product on the market allows for transmitting photo and voice messages.
Original inReach Mini on left, inReach Mini 2 on right. They are basically identical, from the outside. The second version has everything we loved about the original, and more.
Credit: Jediah Porter
There are four major types of non-emergency messaging:
1) Two-way texting with or without location data attached. This is, of course, the most useful.
2) Manual “OK” messages are transmitted, usually with location data attached.
3) Automated tracking. Automated tracking is a function in which the device will send location information to a front country correspondent on some predetermined time interval, signal allowing.
4) The Garmin inReach Messenger Plus allows for sending and receiving photos and short voice memos.
In addition to all the other types of messaging. Various sorts of messaging can go to web interfaces, apps, text messages, and email addresses.
The Garmin GPSMAP 66i provides all the basic forms of non-emergency communication. As does the inReach Mini 2 and Messenger. Similarly, the SPOT X, Bivy Stick, ZOLEO, Motorola, and Somewear Global Hotspot offer all the above forms of non-emergency communication. The SPOT Gen4 has fewer options for non-emergency communications. It has a pre-programmed “OK” message functionality, with location data attached and a few different tracking mode configurations.
Understand satellite coverage limitations before relying 100% on your fancy new device. Steep terrain is often problematic for all kinds of satellite communication.
Credit: Jediah Porter
COSPAS-SARSAT personal locator beacons do not offer much in the way of non-emergency communication. The ACR ResQLink View and Ocean Signal rescueME PLB1 provide no explicit non-emergency messaging. That said, through an inexpensive subscription to “406Link,” you can replicate an informal “off-label” non-emergency message protocol. This service leverages a device “test” procedure to send notifications to friends and family, sometimes with location data attached. These “test” messages imply, “I am here, and my device works.” The test message could imply whatever more you and your informal emergency response network determine in advance.
The award winning inReach Messenger device and associated Garmin Messenger app. In use.
Credit: Jediah Porter
This is nuanced. It is worth noting that ACR once suspended the operation of its 406Link program for years, and their service description explicitly states that it “is not a 'check-in' or 'I'm ok' service.” However, in the same description, ACR implies that it might be used as described above. It is currently operational and, with a full understanding of all the involved parties, could provide a bare-bones sort of non-emergency messaging. Do your further homework on its limitations and functionality.
Apple's Satellite SOS service on all the iPhone 14 models is a ground-breaking advancement in wilderness comms. It isn't perfect. Read our full review of the iPhone service for further elaboration
Credit: Jediah Porter
Apple's iPhone (Model 14 and newer) includes basic two-way texting and a rudimentary form of check-in messaging.
You might picture typical backpacking adventures when you think of a satellite messenger. But remote travel of any kind proves their utility. On a service farming trip in rural Puerto Rico in January 2019, we used satellite communications to coordinate logistics.
Credit: Jediah Porter
On the topic of non-emergency messaging, we have to make one further distinction. Of the products and services offering two-way messaging, some of the newest options allow their messaging app to work seamlessly on satellite signal and cell/WiFi. With the apps from ZOLEO, Garmin, Motorola, Apple, and Somewear Labs, you can have one conversation that moves with you from satellite signal to cell and WiFi. (From Garmin, only the latest devices --Messenger, Messenger Plus, Mini 2, GPSMap 67i-- are compatible with the app that provides seamless messaging. Older devices use an older Garmin app that does not support seamless messaging). This is very nice for smooth communication on trips and for people who frequently go in and out of the wilderness. The SPOT and Bivy Stick apps do not allow sending and receiving messages over cell/WiFi. It might seem minor, but this seamless messaging can greatly smooth communications in certain settings — like international travel or thru-hiking. You're in and out of signal but want to participate in one clean, uninterrupted text chain with someone. The ability to do this has raised the bar regarding what we expect from our satellite messengers; we now wish all of our satellite messenger apps allowed for seamless text chains. Those communicating from home would especially appreciate this; they don't want to jump between messaging apps or contact entries if they don't have to.
On a long thru-hike having seamless messaging from your satellite device app (maintain the same text thread with satellite, cell, and wifi connection) is a great boon to the efficiency and clarity of your communications. Zoleo and Somewear offer this seamless messaging. Others do not.
Credit: Jediah Porter
Signal Coverage
Each of the four satellite communication networks has coverage limitations, and all satellite communications have inherent restrictions. Additionally, we found differences in the reliable transmission of sent messages, even when coverage seemed intact. Because all remote communications are fraught, communication reliability is greatest when it can be “two-way.” We know from experience with one-way devices that the field user can “ send” messages that no one is getting. When the communications are “two-way,” confirmation of receipt is a little clearer.
Satellite Coverage
Terrain, vegetation, structures, and electronic interference all compromise message transmissions. These terrestrial variables are important regardless of your communication network or carrier and can determine your communication reliability. Some places have no satellite coverage ever. Other places will have windows when the signal is in and out. Few places have universal, perfect satellite coverage.
For reasons we hope are obvious, we could not and did not test the coverage and effectiveness of SOS messaging. Each device allows a test mode, which does not activate the entire SOS system on any device. Those of us who have not yet had a backcountry emergency have to trust the manufacturers and the experience of other less fortunate users. For these ratings, we rely on research and SAR consultation.
The ResQLink View and rescueME PLB1 use the same network and communication protocol. These can be tested, but the life of a built-in, non-rechargeable battery limits the number of tests. All these “COSPAS-SARSAT” devices confirm functionality with on-device lights. This is limited in its ability to comfort you, as it doesn't involve satellite confirmation. Some also provide rudimentary test procedures that confirm the signal's actual transmission, but this drains the battery and sometimes costs more. Decades of history and anecdotal evidence confirm the global coverage and effectiveness of the COSPAS-SARSAT system that these devices employ. Aside from institutional knowledge and the basic on-device testing we performed, we cannot test the signal coverage of these three emergency-only devices.
The flip side of those Insta-famous destinations and photos is the tougher communications they might entail. You won't see high level wilderness communication planning on the influencer's pages; that's why we're here.
Credit: Jediah Porter
The other options are easier to test for range and coverage using their non-emergency communication options. Our goal was to verify manufacturer claims. We found that, by sending non-emergency messages from each, all work as intended. The GlobalStar satellite network used by SPOT brand devices and the iPhone covers an American adventurer's major terrestrial wilderness destinations. Within the limitations of the GlobalStar network, Apple service is limited even more than that of SPOT devices. The inReach, Bivy, ZOLEO, and Somewear products use the same Iridium satellite network with global coverage. Within the inherent limitations of all satellite communications, these Iridium networked products work everywhere we've tested them, from California beaches to NE forests to Alaskan glaciers to Patagonia cabins.
With the newest update, the SPOT X includes Bluetooth functionality and an associated app, increasing the overall utility of this model.
Credit: Jediah Porter
The latest entry to the market is from Motorola. The Motorola Defy Satellite Link is manufactured by a smaller company called Bullitt. Bullitt licenses the Motorola brand to sell their product. Bullitt also works with Motorola to sell Motorola smartphones with built-in satellite connectivity. We did not test this smartphone. The Bullitt/Motorola products, including the Defy device we tested, use a different satellite network than the one we are accustomed to testing. As noted above, most of our devices use one of three proven, reliable satellite networks. New products, up to this point, have leveraged existing satellite networks. Motorola/Bullitt branch out further. They use a satellite service called Skylo. Skylo is an intermediary that contacts a host of satellite communications hardware providers. This is how we understand Skylo to work: Many private-sector communications satellites are up in the sky. A bunch of them cover the whole world and are owned and run by Iridium. Another whole bunch covers the inhabited latitudes and continents and is owned and run by GlobalStar. Then there are a bunch of individual satellites and smaller networks of satellites at various orbit elevations that serve different purposes and industries. Skylo works with many of these “other” satellite businesses to connect terrestrial Motorola devices with overhead satellites.
Dense foliage in the otherwise (ostensibly...) innocuous small wilderness forests of the US East interfere significantly with satellite connectivity. In testing, we have found forests dense enough to entirely block all satellite signal.
Credit: Jediah Porter
One of your Motorola Defy messages might go through a low earth orbit satellite owned by company x. In contrast, the next might go through a geo-stationary, higher satellite owned by company z. Skylo works all that out on the back end. Theoretically, this allows comprehensive coverage. In practice, Motorola/Bullitt and Skylo provide a coverage map on their websites that suggests coverage over all of North America and Europe. We have yet to test Motorola in enough places and contexts to compare the satellite networks we know better thoroughly. The “big three” satellite networks are proven and established, and we have deep institutional knowledge of their coverage and limitations. Skylo is newer. In our decade of testing, we watched one satellite communication “innovation” come and go. Any of these businesses and technologies can come and go, but we have more faith in those that have proven their durability over decades.
We also found subtle differences in message integrity. In a host of head-to-head tests, the Iridium networked devices are faster and more reliable than the GlobalStar devices, even with what should be equal overhead coverage. Different devices, even from different brands but on the same network, had signal speed and integrity that were statistically equal. Again, we found no difference between messages sent or received to and from devices on the same satellite network.
Getting a good “fix” on a satellite with your iPhone is challenging. More so than with a dedicated device.
Credit: Jediah Porter
As noted above, satellite connectivity is mainly a function of terrain realities and chosen satellite network. With the introduction of non-emergency satellite messaging to the iPhone we now have also to discuss the ramifications of antenna size. Dedicated devices (like most of what we review here) have relatively large antennae. To include a satellite antenna in a smartphone is to shoehorn it among a great deal of other hardware. The satellite antenna in the iPhone is quite small compared to the other options we review. To optimize the connectivity of that small antenna, the iPhone satellite antenna must be aimed very closely. Other devices do not require this in the same way. The iPhone is equipped with on-screen prompts to help you aim it, but this does add complication and time to your communications. Aiming and connecting to satellites is a big part of texting via satellite with your iPhone. It is a big enough hassle that satellite texting from an iPhone is best considered a rare and novel method of low-frequency, special-circumstance communication. You won't text back and forth as readily with your iPhone as you will with a dedicated device.
Garmin has changed their app landscape. With the latest Garmin satellite communication devices realize that you can update some software and change to the “messenger” app to get seamless texting across satellite, cellular, wifi.
Credit: Jediah Porter
Ease of Use
The combination of setup procedures and in-the-field user interface matters largely determines the ease of use for this equipment. It's worth noting that we're evaluating both the on-device interface and the included networked app interface to get a complete picture. While messaging function and coverage issues are important factors impacting the overall ease of use, we're assessing, comparing, and ranking those elsewhere in our review.
First, let us look at the setup of each device. The COSPAS-SARSAT devices — the ResQLink View and rescueME PLB1 — have identical setup procedures. You fill out an online form and await the arrival of your free registration sticker via mail. You can make changes down the road if needed through the online interface.
Setting up the SPOT, Bivy Stick, Somewear, ZOLEO, Motorola, and Garmin inReach devices are similar. All require you to select and activate a subscription plan.
Another size comparison of these two performers.
Credit: Jediah Porter
The COSPAS-SARSAT personal locator beacons are super simple to use. For most people in most settings, the device will live in your emergency kit for years and years with no changes, maintenance, or deployment. The batteries are fixed and long-lasting. Few will use the device since the only features are for emergency use. All of these we tested have rudimentary instructions printed on the device. The instructions are accurate and effectively comprehensive.
For SOS use, the SPOT Gen4, SPOT X, inReach Mini 2, ZOLEO, Somewear Hotspot, Bivy Stick, Motorola, and Garmin GPSMAP 66i are almost as simple as the COSPAS-SARSAT devices. Activate the SOS mode from either the device or from the app. You can send a pre-programmed “OK Message” from the app of many of the two-way messengers. With the SPOT Gen4, you must send the OK message from the device itself. With inReach, the SPOT X, ZOLEO, and Somewear Hotspot, you can send an OK message from the app or the device itself.
A comparison of the guarded SOS button on the inReach Messenger and the unguarded SOS button on the Motorola Defy Satellite Link
Credit: Jediah Porter
Let us discuss SOS buttons and inadvertent triggering. Unintentional, undesired triggering of SOS functionality is bad. As in any emergency reporting setting (crime, fire, etc), a “false alarm” has serious repercussions. We don't want to be part of falsely requesting a costly and dangerous emergency response to the wild. Any device/service with an SOS function is vulnerable to false alarms. Parents of toddlers who have somehow called 911 from smartphones know what we are talking about… Because of the severity of an SOS false alarm, we need to consider the technological and physical protection of that SOS trigger. Digital activations (from within messenger apps) require some “two-stage” activation. “Are you sure you want to call for help?”. Physical buttons on most devices have a latched/secured cover for the SOS button.
The SOS button of the inReach Messenger Plus.
Credit: Jediah Porter
Most, except for the SOS button on the Motorola Defy. The SOS button of the Motorola Defy is entirely uncovered.
The power button and check-in button are also included. If the device is turned on (as it would be when you are texting or tracking. It can also inadvertently be turned on by the exposed power button), the SOS button could be unknowingly pushed or bumped. This is unacceptable. Suitably protecting that SOS button without modification is impossible. Protecting that SOS button, with design and manufacturing, would have been very simple; Motorola included a cover for the USB charging port. Why not include a similar cover for the SOS button? We aren't alone in noting concern for this potentiality; other reviews online mention the same possibility. We are in the process of testing improvised “solutions” to this potential problem. In the meantime, we cannot recommend using (and couldn't confidently test some functionality) the Motorola Defy Satellite Link. If, through reliable tinkering, third-party parts, or a Motorola/Bullitt aftermarket adaptation, you can gain some confidence in the security of the SOS button, the Motorola should be on your radar. If not, wait until we all get some better information/solutions. Any solution would maintain the compact and light stature of the Defy; it is tiny and light. We like that.
Tracking speed records ("Fastest Known Time" or “FKTs” for short) is an emerging and important use of satellite communications. For these purposes you want simplicity, reliability, great web interfaces for the spectators, and really long battery life. The SPOT Gen4 could be a favorite in this realm, as could our top-scorers.
Credit: Jediah Porter
Using the two-way, customizable messaging attribute of the Garmin Mini 2, Messenger, and GPSMAP, SPOT X, Bivy Stick, ZOLEO, or Global Hotspot requires further effort but is well worth it. Sending customized messages directly from the inReach devices is slow but works. None of the other two-way messengers can send or view messages without the app. On any of these devices, sending customized messages from the app is far more user-friendly than the on-device messaging of the inReach satellite messengers. In this context, using your smartphone's familiar keyboard leverages the best attributes of the inReach, Bivy, ZOLEO, and Somewear options. The SPOT X is usable with its app or entirely stand-alone. The device has a built-in, physical QWERTY keyboard. This makes it the easiest two-way texting device to use. The ZOLEO, Bivy Stick, and Somewear do not allow users to customize non-emergency texting without a smartphone. With the ZOLEO, Bivy Stick, and Somewear, you can still send a basic “I'm ok” message if you lose the function of your cell phone. Ensure your at-home team understands what this means before your travels. Sending messages from either inReach device is tedious but doable in a pinch.
Bluetooth connectivity and smartphone app reliance introduce a potential failure mode to your backcountry communication system. All three Garmin devices, Bivy Stick, Somewear, SPOT X, and ZOLEO have Bluetooth and app connectivity to your phone. As you know from routine smartphone use, Bluetooth and apps inherently have potential issues. This baseline of potential unreliability is uniform across the board and is exaggerated by backcountry communication realities. Apps can be deleted from your phone, and Bluetooth connections can be “forgotten.” You cannot re-download a lost app away from WiFi and cellular data in the wild. If the app relies on a web-confirmed account “login” and that “login” is interrupted, you can't reconnect in the wild. What have we found when comparing this “digital reliability” across app-enabled devices?
Texting on the physical keyboard of the SPOT X device.
Credit: Jediah Porter
First, assuming that the likelihood of app failure is never zero, we will look at the consequences. The SPOT X is the best if you lose your app functionality. It has a large screen and a full QWERTY keyboard. The next best are all the Garmin devices. With all three of the Garmins we tested, you can perform all of the functions, albeit slowly and on smaller screens. The Bivy Stick allows you to trigger SOS, send a check-in message, and activate tracking without the app. All texting requires a smartphone. ZOLEO allows SOS activation and sends a check-in message to the device. The Somewear Labs Hotspot allows only SOS activation on the device.
Waiting for signal on the iPhone. It takes dozens of seconds, to minutes, to get a connection in the best of conditions.
Credit: Jediah Porter
Next, what about the likelihood of an issue? First, we had no spontaneous app/device connection failures in our testing. All our testing was intentional “sabotage,” if you will, of the connection. The Bluetooth/app connection of the ZOLEO is robust. The only way we could get it to fail was to make a multi-step, in-signal process of “delete app account.” On the Somewear Labs Hotspot, we got the Bluetooth to disconnect but could reconnect without a signal. If you log out of the app, you need a signal to log back in. The SPOT X Bluetooth connection is similar to the Somewear Hotspot's. All Garmin products behave similarly. Bluetooth connection can be interrupted but regained in the wild. If you log out of either of the Garmin apps, you need WiFi or cellular to log back in. Though we haven't experienced it, we have read reports from other users of backcountry failure of Garmin app login, resulting in reliance on the on-device functionality alone. The relative likelihood of app/Bluetooth failure is hard to ascertain, as there are many more user hours on the Garmins than on the others. The bottom line is that the few failed inReach/app connection accounts aren't enough to draw any real conclusions from.
Wilderness travel is a high consequence environment. Make sure your equipment is up to speed and that you understand the use and limitations of your satellite communication device and service.
Credit: Jediah Porter
Portability
Going to the wilderness usually requires packing light. Therefore, the portability of your communications device(s) is important. Portability, for our purposes, is a function of weight and bulk.
The Garmin GPSMAP 66i is large compared to most devices we tested, but it also does much more than others. We didn't mind the bulk until the inReach Mini came along. The Mini is less than half the size of the GPSMAP and does nearly as much. The inReach Mini 2 is the same size and shape as the original Mini and does all the important things the larger device does. The Bivy Stick is about the same size and weight as the Mini 2, and the inReach Messenger is slightly heavier.
The Bivy Stick with a compact multi tool for size comparison. This thing is really small, in league with the smallest options on the market.
Size comparison of the SPOT X and inReach Mini. Clearly, the Mini is much more, well, miniature.
The ResQLink View is heavier than the inReach Mini 2 and Bivy Stick and does little more than the ultra-tiny OceanSignal PLB1. The Global Hotspot and ZOLEO are almost as portable as the Mini 2. The SPOT X is similar in size and weight to the Garmin GPSMAP 66i. The SPOT Gen4 is about the same size and weight as the Mini 2 or Bivy Stick. Notably, the SPOT Gen4 is slightly heavier than the Gen3, which is odd. We normally expect newer products, especially products with less function, to be smaller than their predecessors.
You will likely have a smartphone with you on your outdoor adventures. If that smartphone is an iPhone 14 or newer, you already have emergency satellite communication and a form of rudimentary non-emergency communication. This is perhaps the ultimate in “portability,” as sat comms are built into your ever-present pocket computer.
The Motorola Defy Satellite Link is tiny and light. It is less than half the bulk of its nearest close competitor and only a little more than half the weight. We like this. This is a very portable piece of equipment if you can sort out a secure cover for the SOS button (as described above) without appreciably adding to the weight and bulk.
Wilderness adventures of all kinds (and adventurers, and loved ones of adventurers) benefit from at least basic satellite communications.
Credit: Jediah Porter
Conclusion
The satellite messenger market is ever-evolving and we look forward to bringing you the latest backcountry communication devices.
