5 - 30 minutos
iPhone 4 Battery died ... Apple wanted $79 to replace it. Your cure was far less if I had the fortitude to dig into my phone.
As demonstrated in the video, it was a piece of cake. Oh, Apple said their battery was more expensive because it was proprietary ... the battery supplied by iFixit is exactly the same battery that Apple uses.
When you install the new battery, the phone may fail to start because the new battery wasn't charged. It gave me cause to worry for a moment but then I plugged the phone into the charger and it woke up as usual.
Also, I was pleased that in replacing the battery, I lost none of the information in the phone. I'd always suggest backing up your phone before an operation like this but I didn't need to "restore" any of the data.
Phillips #00 Screwdriver
P2 Pentalobe Screwdriver iPhone
iPhone 4 Replacement Battery