During our outing to Barney Riley I had my Garmin 270 lockup on me. I couldn't figure a way to reboot it and you can't take the battery out of that version so I was out of a GPS until its completely full battery discharged (overnight).
When it died, we still had another GPS in the other vehicle, paper maps, and 2 android phones with the 'tracks' application loaded. So we still had decent compasses and made it there ok.
This got me thinking. The android phone should work well as a 'backup' GPS. I'm starting to workup another GPS based app and decided I'd do something like Garmin GPS V functionality for it.
So. to start it would be able to:
2.) GPS location (both notations, found our maps had one and the application had another).
3.) ability to lay and follow gps tracks.
4.) Tempted to make it have the ability to upload your location/tracks to some website whenever it finds that it has connectivity (sorta like google latitude, but also include the history since the last update). If you managed to have an accident and were at some point in cell range it might give someone a place to start looking. Could also be used to share tracks easier.
From there I'd probably be able to get it to 'cache' the google maps terrain and sat images for an area when it had a connection depending on how much sdcard space was left. This would be something you'd have to do before you lost cell access though.
So, what other features would you guys like to see in this if you would end up using it? The main limitations I'm working with are
1.) Really can't real time road nav off of maps. Google won't let you use their stuff and a full map kit to distribute is prohibitively expensive for the first go round. I'm also trying to make this a cheap toy/backup application not a primary nav application.
2.) Needs to be able to work most of the time away from the cell network.
Any input would def be appreciated.