2 - 5 minuten
My phone was always well taken care of, my wife on the other hand goes through smart phones very often, I made the mistake of letting her handle it for a FEW MINUTES and that was the end of my screen. She dropped it on concrete flat on the front panel and it landed on a pebble that caused a spider crack on the whole front(see pics) luckily I knew about ifixit I had previously changed the battery so I figured why not try the screen!
Ok so the repair time is estimated at 1 hr but if you are doing his for the first time be prepared to spend anywhere from 2 to 4 or even 5 hours if you are like me and made little mistakes along the way as a tiny misplaced or displaced item can have you backtracking and pulling everything apart again.
Separate and label everything it is the biggest time saver and headache preventer. I did it as a spur of the moment thing after getting my package and I was maybe 75% organized and it took me about 3 hours. I made my iphone go from black to white for a change of scenery and voila it's just like new again. Thanks you guys at iFixit you guys rock.