10 - 30 minuten
My iPhone battery no longer held a charge.
Altogether, the fix took 20 minutes. When I turned the phone on, though, it wasn't finding my cell service. Following the advice of others who've done this repair, I connected the phone to my laptop and downloaded the latest operating system. It took hours to update, but once it was done, cell connection was established.
As other have said, work in a clean place with lots of light. The parts are TINY. I used a high-intensity lamp designed for tying flies as my light source, along with my strongest pair of reading glasses. Look carefully at the photograph that shows the grounding clip. It's held in place by one of the screws you remove, and it will take some manipulation to get it back in the correct position as you attempt to insert and tighten the screw. One other note: be patient in prying up the battery, which is held in place by adhesive. It will come loose if you keep gently prying, moving the prying tool back and forth along the outside edge of the battery.