I would like to know your opinion about updating iOS 7.1.2 to iOS 9.2.1 Until today i use ios7 because it's faster and it consumes less memory. My iPhone 4S has only 8GB and i'm afraid don't have enough free space as before. If i update i plan to restore the phone to factory defaults. Do you know how much space will be free on my iPhone after this procedure? Is iOS 9.2.1 friendly to iPhone 4S in general? Does ir compensates update? Thanks to all!