I found a post which lists some "battery saving" myths for android phones. The one I found most interesting was the one explaining how Task killers are not necessary because.... Android automatically kills a task when more memory is needed. Android automatically kills a task when it’s done doing what it needs to do. Android automatically kills a task when you haven’t returned to it in a long time. Most services (while possibly running in the background) use very little memory when not actively doing something. Killing certain processes can have undesirable side effects. Not receiving text messages, alarms not going off, and force closes just to name a few. Most applications will exit themselves if you get out of it by hitting “back” until it closes rather than hitting the “home” button. But even with hitting home, Android will eventually kill it once it’s been in the background for a while. I thought I would share the link to this with all you Xperia users, as I notice alot of people questioning what they should and shouldn't use to save battery! Busted: 5 Myths About Increasing and Decreasing Android's Battery Life Hope it Helps!