I am using iPhone 4s since Feb-2014. There is heating problem with the set. It's got heated up like that even you can not put your set near to your ear. I got the set replaced in the month of June. I still facing heating problem. There is also problem that apps are getting crashed. I called apple customer care many times. They were giving me a funny answer like having metal body and using facebook and whatsapp type of applications, I am facing such problem. I asked them that if I would have used mobile only for calling purpose then there would have been no need of taking smartphone. Every time when I call customer care they have only one solution i.e. restore factory setting. Restore factory setting takes at least 2hrs, so it is not possible for me to do the same everytime. I already told them that if iPhone 4s is not supporting iOS 8 or there is any problem then accept it. Even I am ready to upgrade my iPhone 4s into iPhone 5s and ready to pay the margin money. They suggested me to go to service centre again and again which is not possible for me to leave my phone for 5 to 7 days to rectify the problem because I have already done that and the problem is still as it is. Even they are not providing any backup set for during those period. I am really fed up with this set.