Yeah, its time without a signal that drains the battery. I also found that I had a nasty kernel wake lock that was keeping my phone awake for about 4 hours while the screen is off. This meant battery used by Android OS was like 12%. Apparently using a static IP solves the type of wake lock I had, so I've tried that. Hope it works!
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Another feature I'd like is Androids multitasking switcher. You get to scroll vertically between previews of apps and simply swipe to close them. Its quicker than using wiggle mode!
Im almost never without signal. Its the actual radio on standby thats using loads of battery.