20 - 30 minuten
I chose to replace my battery after significantly degraded battery life through years of constant use. That, and it annoys me when batteries hold a charge like they should.
So I bought a super cheap battery and replaced it. That worked fine for a couple of months, until it gave me the "black screen constant rebooting" error all the time.
I chose to replace the battery again when this happened -- this time with iFixit's battery!
The shipping company managed to destroy the package and lose the battery. The empty package made it to my door with tire marks on it! I called up iFixit and they shipped another one right away. Very grateful for stellar customer service.
I did this once before, months earlier, but the guide makes this super straight forward. It went swimmingly. That means well.
-Disassemble the iPhone on a non-metal tray to catch all screws.
-Be gentle, but don't be afraid.
-Take your time putting the logic board back.
-Buy the better battery the first time. :P