I bought 4S about 3 month ago. Everything was perfect, until 2 days ago, I noticed that the battery drops faster than before. I have updated IOS to 5.1, do Reset All Settings, and even Clean Install from iTunes and won't help. The question is: 1. Can I claim warranty on the battery? 2. I bought the phone from US online apple store. Now I am currently assigned to work overseas (Singapore) for several months. Is there anyway for Apple to just send the battery only? If I had to buy the battery myself - where is the most trusted place to buy "genuine" iPhone 4S battery? I'd rather buy genuine-more-expensive battery than generic. It seems place like amazon, ebay have been flooded by generic battery and claim as genuine.