15 minuten - 1 uur
Standard issue failing battery, so very common to the iPhone world.
This is the second time i've done this repair, this time for a friend. This is probably the easiest repair you can do on the phone. I had no issues at all. I didn't even refer to the guide this time, though I had it on hand just incase.
couple of things to look out for. when you're taking it apart you have to be gentle but firm; hard enough to pull things apart, but not so hard as to tear it apart in the process. It's pretty stiff, especially if it's never been taken apart before, but there are some pretty fragile ribbon cables in there holding the camera side together for that initial opening. Only other thing, the double sided tape on the battery is a pain in the butt. That old battery will not come out nicely, so if the battery is not what you were planning on replacing, it will be after removing the one in there. Just be careful not to damage anything else around it. Other than that, a super easy repair to make your phone work again.
Side note. There is a reason they don't warranty the replacement battery. I've have the one in my phone replaced for about a year now, and it's showing signs of dying again. food for thought.