1 - 2 uren
My one year old grabbed my wife's 4S off the coffee table and dropped it on the tile around the fireplace shattering the screen.
The repair went extremely well. I took my time and followed the instructions in the repair section of iFixit. Everything worked like a charm. I took my time so from first screw out to last screw in the repair took about two hours.
If you didn't order an extra home button, it may be worth it. That was probably the only section I rushed through and I destroyed the gasket which is extremely delicate. The rear of the button has some sticky stuff so it's in the new display. My only concern is that it may fly out if dropped a certain way. Of course, a screen cover of some sort would prevent that as well.
I used 10 cups with labels written on them for the sizes of the screws. This really helped as they are so tiny. The nice thing about the kit is that it comes with magnetic screwdrivers - I didn't realize they would be magnetic and they made the job that much easier. All in all if you follow the guide, have some patience and attention to detail, anyone can do this with the kit provided.