30 minuten - 1 uur
The original battery in my iPhone was going for well over 2 years and it was getting to the point I couldn't make it through half the day without charging.
I have opened my iPhone before to fix the headphone jack but both times used the guide on here. I opened it up without a problem. Didn't realize some of the screws were different sizes so I had to eyeball which one went where. Battery adhesives snapped quickly so I had to heat and pry the battery out gently with a card.
Use the suction cup to just get a pry tool in to open the front. Don't try to yank the whole front off with it. It will break loose and stuff will rip. The first time I opened my iPhone the guard on the home button connector went flying across the room and I never found it. I was lucky something essential was not broken or lost.
If your adhesive breaks use a lot of heat and patience to get the old battery out. It won't budge until it's almost completely free.
I freaked when my phone didn't turn on immediately but the ifix it battery had absolutely no juice. It took a good 10 min of charging before it showed any signs of life and charged for closer to 30 min before it would boot. I had to put it through a few complete charge cycles before I got any performance out of the battery.