Originally Posted by jimroe

ITA - early 8900s had poor battery life - later OS releases have made a difference. I have one of the first AT&T devices with 4.6.1.231 and the worst I have ever seen at the end of a 24 hour day is 48% battery remaining - if I don't do too much playing around with the device I may have as much as 75% remaining. Talking on the phone seems to take less out of the battery than "fooling around" with it.

There's a lot of power saving features in the late OS versions, including CPU speed controls which may help explain why later versions are better than earlier ones.