When you're out adventuring beyond the reach of cellphone towers – at sea, in the jungle, on the glacier – it's reassuring to think there's somebody back home who knows exactly where you are.
But in order to pass along your whereabouts to friends, family, and fellow travelers (or even search-and-rescue teams) while you're deep in the wilderness, you'll need a satellite messenger. The popularity of these devices has exploded over the last few years. They're very simple – from just about anywhere on Earth, you can press a button and send an "OK" message along with your coordinates to anybody who wants to track you. Pair a satellite messenger with a smartphone via Bluetooth and you can add some additional stuff like short, Twitter-style messages or map data. (If you're wondering how these differ from Personal Locator Beacons (PLBs), REI has a pretty good summary.)
Some of the most popular satellite messengers are made by SPOT. But now, the company is seeing some competition from DeLorme's new InReach device. Both are small, about the size of a GPS unit. In fact, they are GPS units, but they'll only pass along your location to the folks back home. Neither unit has a screen, so they can't tell you where you are while you're in the field.
What they can do is collect your pings and plot your route and latest locations on a map that's accessible via the internet, and send an "OK" message of some sort. Anyone following your adventures can keep an eye on you using these two data streams. Both devices also have SOS buttons to send your coordinates to the International Emergency Response Coordination Center to evacuate you or a member of your party in the event of an emergency.
While they're similar in basic functionality, there are some nuanced differences between the two, and which one you should buy depends on your budget, your messaging needs, and where your adventures are taking you.
I've used previous SPOT devices for the past few years on mountaineering expeditions and river trips in the Alaskan Arctic. I hadn't yet tested SPOT's newest device, called Connect, or the DeLorme InReach, but I got the opportunity to test both of them side-by-side on a recent trip to Peru. I used both devices to send "OK" updates as we moved between Lima, Cusco, Machu Picchu and the rural community where we were building a classroom with an amazing organization called Peru's Challenge.
SPOT Connect
SPOT's latest device, the SPOT Connect ($169, plus $100 per year for the service plan), pairs with your iPhone or iPod via Bluetooth. Download the free app for iOS or Android to your phone, and you can send custom 41-character messages like: "At camp. Wet, tired but doing well." Don't expect any sympathy, though – you can't receive a message back.
The SPOT Connect is compact and only has two buttons: "Power" and "SOS." This way, even if your iPhone's battery dies, you can still send an SOS message to get rescued. Bluetooth is a pretty huge battery-drainer on both the device and your smartphone, so the Bluetooth tether between the two automatically times out after a few minutes of inactivity. If you're sending an OK message every hour or so, it gets tedious to re-connect the Bluetooth link every time. Also, the devices don't always re-connect on the first try, and I sometimes had to restart both the SPOT and my phone to get them to see each other. Once connected, however, I could use the SPOT to send updates to my pre-defined contact lists on my phone, as well as Twitter and Facebook.
The interface with a smartphone is appreciated because it eliminates the need to decipher the cryptic flashing lights on the SPOT. Using the messenger unit by itself, you press the "OK" button and a number of lights flicker, telling you the power is on, battery is good, it sees the satellite, and that your message is going through. You have to study the manual to know what each sequence of blips means. On the smartphone, all that stuff is simply spelled out for you.