How long keeps battery in iPhone?
The battery lasts very varied times depending what you're using it for. Calls, music and applications take up plenty of memory and subsequently drain the battery pretty quickly. As an owner of an iPhone 3G I've had plenty of experience with the battery draining too quickly, leaving me stranded. However, if you are using it as a phone with the occasional application open then i would say the battery lasts about 30-40 hours.