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ZOLEO Satellite Communicator Review

This nearly perfect device provides comprehensive, polished, two-way satellite communications
Editors' Choice Award
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Price:  $200 List | $199.95 at Amazon
Pros:  Excellent network, seamless communication, some on-device functionality
Cons:  No on-device message viewing or composition, no tracking
Manufacturer:   ZOLEO
By Jediah Porter ⋅ Review Editor  ⋅  Apr 3, 2020
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#2 of 10
  • SOS/Emergency Messaging - 30% 7
  • Non-Emergency Messaging - 25% 8
  • Signal Coverage - 20% 8
  • Ease of Use - 15% 7
  • Portability - 10% 7

Our Verdict

This Editors' Choice is polished, effective, and our pick for seamless messaging. The ZOLEO Satellite Communicator enters this market with a mature and excellent product. It isn't perfect, but it brings an attribute that will raise the bar of other options. The construction feels solid, and the subscription options are clean and competitive. We especially like that conversations in the ZOLEO app are continuous across both satellite and cell/wifi signal. We wish that more satellite communication devices and services offered this functionality. Our main gripe with the ZOLEO, and this is likely minor for most of you, is that one cannot view or compose custom messages on the device itself. All customized messaging is done through the app. In routine use, this is fine. However, if something were to happen to your smartphone, rudimentary on-device custom messaging would be nice to have.

Compare to Similar Products

Our Analysis and Test Results

The ZOLEO is a brand new, mature contender in the category of two-way satellite messengers. As a new product from a little-known company, we are pleasantly surprised with the sophistication and polish of all aspects of this product. The ZOLEO has nearly everything we look for in a satellite messenger for wilderness travel. All it lacks is live tracking (which could conceivably be added as a firmware update?) and the ability for the user to view or compose customized messages from the device itself. All customized, two-way messaging must be conducted through the ZOLEO app. Otherwise, the ZOLEO has messaging, satellite coverage, portability, and ease of use that tops the field. It shares our Editors' Choice award with a product that does almost all that the ZOLEO does but also allows two-way messaging from the device alone. Neither EC winner is perfect. Both are excellent. Of the two top-scoring products on the market, the ZOLEO is the one you pick for seamless communication in and out of the field. The app collates one discussion thread, whether you are receiving and sending messages via satellite or via cellular/wifi. The other top scorer doesn't allow this functionality.

Performance Comparison

The Zoleo is a comprehensive  smooth-functioning entry to the field. We dig it.
The Zoleo is a comprehensive, smooth-functioning entry to the field. We dig it.

SOS/Emergency Messaging

SOS Messages from the ZOLEO are sent from either the app or from the device itself. Provided your satellite coverage is adequate, that SOS message is transmitted via ZOLEO to GEOS Inc., a world-wide, private-sector emergency dispatch organization. GEOS notes your location, some basic identification information, and then works to secure local emergency response. That local emergency response varies greatly depending on your location and a whole host of other factors. GEOS contracts to perform dispatch services for the users of most (if not all?) private sector satellite messengers.

Thankfully, we did not have to employ the SOS messaging attributes of the ZOLEO. We like that a help message can be sent either from the app or from the device alone. If your smartphone is damaged, out of battery, or missing, you can still request help in a dire situation. We also like that ZOLEO contracts with a proven, large-scale dispatch agency. Beyond the conclusions we can make based on our understanding of how this technology and service work, we cannot comment first-hand on the emergency messaging of the ZOLEO.

On-device  protected SOS button of the BlueCosmo Zoleo. Use this only in truly dire emergencies.
On-device, protected SOS button of the BlueCosmo Zoleo. Use this only in truly dire emergencies.

Non-Emergency Messaging

In some ways, the ZOLEO has the best possible non-emergency messaging on the market. You can use your familiar smartphone keyboard, and conversations are organized just like in any other modern messaging app. This is fairly consistent across the handful of two-way satellite messaging products on the market.

The ZOLEO sets itself apart with non-emergency messaging that is seamless across different connectivity types. You can have one text chain that works via satellite and via cell/wifi. This is a welcome attribute for those traveling in and out of signal and isn't ubiquitous on the market currently. It seems like a relatively simple software change that may soon come to the services that don't currently do it. Our other Editors' Choice winner doesn't currently work like this, and we wish it did.

You can also send a preset "I'm OK" message from the app or the ZOLEO device. This is similar to other products on the market. At the very least, with this attribute and a good understanding between you and your emergency contacts in civilization, if you damage or lose your smartphone you can still let people know that you are safe.

Our one major wish is that the ZOLEO allowed viewing and composition of customized messages on the device itself. On a small device this is going to be a cumbersome prospect. Typing in the smartphone app will always be easier. Nonetheless, in that scenario in which your smartphone is incapacitated, being able to make valuable and nuanced two-way correspondence is quite valuable. The other Editors' Choice winner allows this sort of messaging from the device itself.

The check mark denotes the button one can use to send a pre-programmed "OK Message". This is nice. We only wish one could do even more directly on the device  without the app.
The check mark denotes the button one can use to send a pre-programmed "OK Message". This is nice. We only wish one could do even more directly on the device, without the app.

Signal Coverage

The ZOLEO uses the global and proven Iridium network for its satellite communications. Our test team has extensive experience with this communication network and can vouch for it. Of the choices for global, two-way communication, it is definitely the best we know of that is available to the private sector.

The Iridium network covers the entire earth but is subject to all the ubiquitous vagaries of satellite communications. All satellite communications require an unobstructed "line of sight" between the device and the satellite it is communicating with. Trees, buildings, and steep terrain can and do interfere. Iridium's "Low Earth Orbit" satellites move overhead, resulting in a signal that comes and goes with time. You might have a connection now and lose it in minutes. You might not see a signal right now, but it could appear in a little bit. In certain terrain (dense forest, inside buildings, deep and narrow canyons), you might never get any sort of satellite signal.

A sampling of the tested devices  showing relative sizes. Clockwise from upper right: ACR Aqualink (discontinued)  ACR ResQLink  Somewear Global Hot Spot  SPOTx  Ocean Signal PLB1  SatPaq  Inreach Mini  Editors Choice BlueCosmo Zoleo.
A sampling of the tested devices, showing relative sizes. Clockwise from upper right: ACR Aqualink (discontinued), ACR ResQLink, Somewear Global Hot Spot, SPOTx, Ocean Signal PLB1, SatPaq, Inreach Mini, Editors Choice BlueCosmo Zoleo.

Ease of Use

The ZOLEO is slick and simple. We had no problems setting it up and getting messages going. Starting conversations, whether from the ZOLEO sender or from any sender in civilization is simple and clean. If the correspondent in civilization equips themself with the free ZOLEO app, two people can correspond with even longer messages than if the civilization correspondent were using just an email address or phone number.

Our test team is well versed in the realities of satellite communications. Our commentary on relative ease of use and signal coverage is calibrated against all satellite communications and is based on extensive and deep testing. You will find other online reviews of all sorts of satellite communication devices and services that indicate profound issues or differences in quality. These reviewers are likely less familiar with the realities of satellite communications. All satellite communications are pretty annoying and slow, regardless of the hardware or service. The ZOLEO does as well or better than most, but will never replicate the ease of texting with cell signal or wifi.


The ZOLEO device is almost as small and light as the smallest options on the market. It feels robust, and all the buttons are secure and weatherproofed. ZOLEO secured third party endorsement of the weather resistance, and it passes to "IP68" level. This means it is certified to be "water-resistant". This is all you should need. Don't submerge it deeply for hours and you'll be good to go.

There are other, smaller options on the market, but not by much. That we are discerning between products that weigh 4 ounces and 5 ounces (the ZOLEO weighs 5.3 ounces on our calibrated scale) would have been unheard of a decade ago. Two-way, wilderness communication equipment that weighs less than your standard apple is something that we couldn't have imagined not that long ago. Sure, it could get smaller, but not by much. We are pleased with the portability of the ZOLEO.

The Zoleo device  in use on a hike in Death Valley National Park. It is compact and light enough to take everywhere with you.
The Zoleo device, in use on a hike in Death Valley National Park. It is compact and light enough to take everywhere with you.


Whether you look at just initial purchase price or full cost of ownership (including service), the ZOLEO is competitive with the average options and not that far off of the best values on the market. Direct cost comparisons are difficult because each company offers different types of service subscriptions and terms of service. We have crunched the numbers on various options with each product, noted those in a graphic in our main review, and can confidently say that the ZOLEO isn't the absolute best value, but for the performance, it is worth the cost.

Sample app screenshot from the Zoleo
Sample app screenshot from the Zoleo


ZOLEO enters this product and service category with an entry that is mature, well-developed, and nearly comprehensive. No one product currently on the market does all that we know is possible. The ZOLEO comes close. All it lacks is live tracking and the ability to view and compose customized messages on the device itself, without your smartphone. If it had these things, it would be alone at the top of the heap. Because no one product has all the functionality possible, we have granted two Editors' Choice winners. The ZOLEO is one of those.

Jediah Porter