Anna,
thanks for stopping by and posting the APP. I just downloaded it.
I do have a technical question for you though. It appears that the GPS in the iPhone only works correctly if the phone has been left on in a coverage area and then moves to an area without cell coverage. The GPS seems to work fine then.
For example, if I shut my phone off and start it in the middle of nowhere Utah, with no cell coverage, the GPS will never acquire sats.
That has just been my experience, no evidence or research otherwise to support it. Maybe you have some suggestions or ideas to help.
I've experienced that a couple of times, like the location unit is just frozen. Totally rebooting the phone will resolve it for me. I don't think it's an issue of no cell coverage, I think it's some bug in the iphone's location code.
It can take the iphone a long time get a gps lock if corelocation is totally off. The triangluation location from cell towers comes in first. Outside my house, I usually get a triangulation signal in about 15 seconds, a +/- 256 ft gps signal at about 40 seconds, and a +/-56 feet about a minute. This varies with location and conditions of course. And apps have different thresholds on what accuracy they require, which is some of the difference in location time that Winkomosis noted. But it's probably more based on the state of corelocation when the app starts than the particular app, since all apps use the same iphone library to get the location.
Gaia GPS will show your location on the map as soon as it gets any location, but won't allow recording a track until the signal is from the GPS and better.