GoPro Hero3 Black went face down on a ceramic tile floor, chipped the lens
I was shocked to see this lens for 20 bucks. Other places online were $100 and up and because of all involved in taking the camera apart, that seemed like too much of a gamble. But 20 was worth a shot. The lens was already attached to the housing and was already in focus. Repair went just fine, used youtube videos to see the process.
The screws are some of the smallest you will ever deal with. Don't lose 'em. And be careful with the ribbon cable and sensor.