how long do batteries last in a 4g
iphone 4g and battery loses power in 2-3 hours. I need a new battery?
iPhone 4, iOS 8.4
The iPhone 4 is getting to be a rather old device, and batteries do wear out over time and repeated charge cycles. You might consider a battery replacement, which I would not have done by anyone but Apple or an Apple Authorized Service Provider - there are way too many horror stories on here about iPhones being damaged by third-party repair folks.
The price is $79: http://www.apple.com/support/iphone/repair/battery-power/