5 - 30 minutos
iPhone 4 went dead after a week of having it dry, then using it, recharging, leaving it on, recharging, then death. After reading the iFixIt and other sites I chose to replace only the battery. I decided that cleaning the logic board on an older unit was not worth it.
Repair was very simple. I have an older iPhone 4 with the standard mini phillips screws, no special screwdriver needed. The iFixIt instructions were easy and thanks for the tip on getting the excessively glued in battery out. It fired right up and all is perfect except... the WiFi is no out.
Check your pockets before washing your clothes.