I had boughten my friends old iPhone 3G off of him for $25. It was old and well used, so it had a host of problems that I decided totals on as a project to pass my time. One of those problems was the poor battery which only lasted 45 minutes. This was the first thing I decided to replace, so I went to Ifixit.com and ordered a kit.
The repair was an interesting experience. I looked up alot of videos prior to the batteries arrival, and I tried my best to be prepared. When it did arrive, I even loaded a video to help me alOng the process. Problem is I didn't realize that it wasn't as easy as it was told to be. The first time (after 45 minutes) I got the new battery in and the phone reassembled, the display wasn't working. So I went and dissasembled the whole thing and reassembled it again. The display worked this time, however the home button was now very hard to get a response out of. So I took the display off ans reconnected it after fiddling with the home button connecters. Then finally the whole thing worked! So it was successful, even if I had to use a exacto knife to get the display off because I didn't have a suction cup. I thought a cup was included in the kit. Oh well I'm still satisfied with the purchase. Thank you guys!
Ifixit has the best, highest quality batteries for the prIce, and they don't disappoint at all. I'll be coming back for all my Idevice needs!