Power demands for GPS updating

[Island Jim]

We hope to update the users location on a map each time that they come back to the main menu. It is likely that a user may have our application running for up to an hour while they are using it. Will actively searching for location coordinates create a significant power drain?

[roiegat]

My wife and I are avid GeoCachers and we use our IPhones for it. GeoCaching essential involves looking for containers based on cordinates given by the person who hid the container.

Since the GPS is on most of the time, I can tell you that it does drain the battery pretty well. I would say using my IPhone 3GS, I could have maybe 2-3 hours with the GPS open at all times.

My wife and I have gotten good at alternating who's IPhone we use, plus we also have an additional GPS as well.

[RobotWoods]

maybe you could have the "go to main menu" button invoke startUpdatingLocation, and then didUpdateToLocation could stopUpdatingLocation and take the user to the main menu...then it wouldn't be continuously searching (but would have a lag when you hit the button while the location was gathered)? Just a theory since you didn't mention if you need location data aside from that one use.