>I got the impression that when paired up with a smartphone it was better than good enough.
[This is likely too long of a review for somebody really new to this device]
After reading this post, I did something to cause my device to want to activate again, and it appears like the Earthmate app is getting GPS data from the device even though I can't use the device itself (not sure if that means the GPS through bluetooth would work without a subscription plan). Although, even if it might be working without the device activated, the weight of it, makes me think it would be too much of a brick to carry only to augment a phone's GPS accuracy.
I haven't been using the map software much, but too many times when I tried to, the Earthmate bombed out on my Samsung s5 Active. The android app store reviews would lead me to believe this is the case for most Android users. A reinstall fixes the problem, but then I have to redownload a minimum 900mb of maps, not something I ever want to do on my data plan if WiFi isn't an option.
Worse for some people I'd imagine, is when it does work, the Earthmate maps seems to show only the most prominent trails systems. Other than places like Yosemite, the Earthmate maps sometimes has zero or only partial trail information and even the fire roads are incomplete. My 2008 24k Garmin maps are much better (and I thought they sucked), Google maps even looks to have more trails than the Earthmate map.
Worse than that, is I used it once to see how much further an established trail junction was, only to have Earthmate make me believe I had somehow passed it, but my surroundings didn't quite match up to what I was seeing on the topo (yet). Later that day, I looked at my breadcrumbs and all looked well, like it hadn't shown me passing the junction. Also had a situation where it had me on the wrong side of a creek while I was hiking, but when I went to look back at that recorded track later, it was corrected, like it hadn't shown me on the other side of a creek for 20 minutes. Which causes me to wonder if there is something about the how the map displays live location data that is out of wack. Both times I pulled up GaiaGPS, and that showed me right where I expected myself to be.
On the very positive side, the inReach does what I bought it for very well. Which is to allow me to send detailed messages and location updates to family. As I frequently find myself wanting to do something other than my planned route or taking an extra couple days. So, it's great to now have the freedom to go where I want last minute and extend a trip, without worrying that people will think I went missing, or if I have gone missing, they may look for me in the wrong place. All the other stuff would be nice, if it worked, but it isn't what I bought the device for. It is also fantastic to be able to confirm the message has sent, and then turn off the device and save battery power when 100 hours isn't going to be sufficient.