Camping

[glatt]

I've never used the apps, but my understanding of them is that you download the maps from the app (paid) and then you can turn off the cell signal and wifi to save batteries. You turn on GPS only, and the GPS tracks you in the downloaded map on the phone. There is no SOS feature.

I'd be curious to know how the GPS units you are talking about send an SOS. Do they use satellite phones? I've heard of the inReach. My sister has one of those that she uses when she and her partner are hundred of miles from the nearest road. It lets you send text messages for like a buck a text, using satellite service.