Sorry about the late reply.
I have any number of apps that use gps. I've noticed that google maps is often on in the background (when checking what's using the battery), even though I'm not using it.
I'm also wondering if my gps program was on as well.
Its normal for Google Maps to show, your not looking at active applications but services and processes. Services and processes work in the background, some will be related to your homescreen, email clients polling, some to do with location like maps et cetera.
Its pointless using a task killer or manually stopping them because the OS or another application will restart them and that kind of defeats the object.
Just remember, Android isn't like Windows in that it doesn't require free RAM to start applications. It borrows the RAM needed from else where, closing something the system thinks isn't needed.
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