10 - 30 minuten
My iPhone 4s battery was 19 months old and seemed to be losing charge faster than it used to. In fact, it no longer made it through a typical day without stopping for a refresher charge somewhere. So, I decided to replace the battery to see if this would give me a full day's use since I was about to hit a week of trade show work.
The repair went fine in the end. In all immodesty, I would say I'm pretty good at this kind of work. There are a couple things that were a bit of a hangup, and these had to do with my age and eyesight coupled with the tiny, tiny screws that Apple puts into their product. This mostly resulted in just taking about 30 minutes instead of 10 minutes.
BTW, in the end, my battery life didn't go up as much as I'd hoped. The hope had been 2x, the reality was more like 1.2x. This is just enough to make it through the day, which is good enough, but not spectacular. As a result, I have had to make sure I manage my phone well to have margin (e.g. shut down bluetooth when unused, etc.).
So, here are the things you should know:
1. If you have 50+ year old eyesight (I'm 58) you may want to consider having some sort of optical aid to see the tiny screws in the iPhone. The two outside screws on the bottom of the phone (e.g. the pentalobes you are going to replace in the process) are NOT the problem. It is the two tiny, tiny screws inside that hold the battery clip on. They are 0.2mm diferent in size and are tiny to begin with. Hard to see and almost impossible to sort out if you mix them up. Therefore, a stand-alone magnifier would be helpful.
2. Keep the parts in either a parts tray or stuck to some tape. It's too easy to lose them.
3. The ground clip that is removed after you remove the battery clip screws is tiny and not that well documented in the iFixit instructions. i thought about this and think it's because it is so small that you need to have a pretty decent macro photography setup to show it clearly and nobody has taken the time. In any case, you should use your magnifier to take a close look at the placement BEFORE you take it apart because it is painted black, it blends in, and you need to carefully note the way it sits. The larger photo of the iPhone insides makes it look like the tip goes into the phone instead of out towards the back cover. I suggest that a better detail photo would be helpful if someone can do this.
4. Bring tweezers suitable for handling 1.3mm screws. The instructions do not mention this, but I think many folks would not be able to handle these without tweezers.
5. Make sure you are at your least shaky. Seriously, you need to plan around your coffee, etc.
In the end, the iFixit instructions were invaluable. Adding the above info will be helpful for any geezers out there like me. :-)