CastAway makes all good points. <br><br>I think the key here may be whether the emphasis is on urban/suburban or rural/wilderness survival. For the former, the addresses of friends, relatives, a hospital, or the phone number of a cab company might be crucial, for the latter, we seem to be stretching it's usefulness.<br><br>I’m not too terribly concerned about battery life, as I always carry the “next” set in my pouch, and have resisted (so far) the rechargeable versions, partly because of that. The lack of water resistance and durability are issues. It’s probably more durable than one might expect, but not like serious outdoor gear. I have 3 waterproof cases of various designs for mine (for sailing, mostly) one of which allows some use of the device while enclosed, but they are all less-than-perfect compromises. It’s clear that, for whatever reasons, the computer and consumer electronics industries consider “ruggedized” products a small niche market. Too bad.<br><br>For urban/suburban survival use, though, it’s worth pointing out that it can hold FAR more relevant information than it’s equivalent weight/bulk in paper. I know- I used to use a large Day-Timer, was constantly running out of space, and didn’t have a tenth of the information I have now.<br><br>For pure rural/wilderness use, I have to agree that it’s much more doubtful. I take it car camping, and often on day hikes (which is arguably almost suburban in the East), but I probably wouldn’t take it backpacking, where I really am counting grams. Most of it’s possible functions in the woods are probably better performed by paper or a dedicated device (star charts, GPS, compass).<br><br><br>