Cracked rear panel
The easiest and most gratifying repair one can do themselves.
Tiny bits of dust on the black interior of your phone will now drive you nuts-as will the fingerprints and smears on the glass. Be prepared to remove the glass a few times to chase down these annoying little problems-it's worth the trouble. A micro-fiber cloth is a must, but if you're really into it, cloth gloves will make you a pro. It might also get you a sweet assembly job at Foxconn. Holding the transparent back up to a really good light source and viewing it against a black surface, like the old back you're replacing, will help track down smears. I had a really stubborn bit of smear on the inside of the lens port (probably from rubbing against the rubber seal) which required a little Goo Gone applied (sparingly) with a cue tip.