>This will make PLB (personal location beacons) redundant

Wouldn't this make the subscription satellite communications devices like inreach redundant, rather than PLBs? A safety conscious person in the wilds would probably still want a dedicated emergency device (?), only now it has another possible communication method to make it even more reliable.

PLBs as I understand it are designed specifically to be one-shot foolproof devices with no secondary comms, with guaranteed battery lives (15 years I think), robust cases etc. that just sit there until you press the 'Save me' button. A phone (or inreach which is closer but still has messaging etc.) is not a real replacement for that functionality as I see it. Mainly because the other things you use it for mean it can run out of batteries or whatever.