I have an application that runs on Windows Mobile and uses GPS to update its location at various intervals. As expected, turning on the GPS chip increases power consumption. (no duh ..)
So, currently my method is to turn on / off GPS for approx. every 4 minutes to get a location, do something if something has changed, and update its location on the Internet only when necessary. Otherwise, turn it off again and wait.
On my one-year-old HTC Touch Diamond phone, with a new charge, leaving the screen turned on (but darkened), + WiFi, and doing nothing, but letting him sit there, I got a maximum of 6 hours from him.
This is "normal", but using GPS easily reduces the rating to 2-4 hours of normal "real" use (YMMV).
Another option that I was just thinking about is for the web server to signal the phone instead to update its location when necessary, instead of the phone just doing it blindly.
Thus, the phone uses only power to connect to data and check the server. If the server reports an update, only then will it turn on the GPS.
Except that the response time is much slower (I expect), and if the phone is somewhere, it cannot receive a stable update, then you will not even know its latest location. At this point, you are stuck waiting.
I was hoping the phone would be more autonomous.
, ?
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