Corrosion on the charging port and optical sensor, battery cover coating completely peeled away, and battery cover separating from the band. I'm not an extremely active person (I don't go to the gym and workout or anything), I never wear it in the shower, and I take it off whenever I do any activity where it might get damaged (i.e. yard work, automotive maintenance, etc.) I've babied this thing and it's falling apart on me. I tried to get service on the website and I tried to explain it over the phone. They weren't willing to help me unless I paid for it, even though everything I've described is a known issue and documented. It's still in warranty for two more months.