I just bout a iphone 4 i used to have 3 droids... droid... then droid 2 then droid incredible... and i was wondering what are the maintence like you know thing you have to do to the phone to keep it good... like you know in a car you have to maintaine it.. do i have to delete my messages call history internet history and stuff? if i keep my call history will it slow it down? or about my messages? text messages do i have to delete them periodically to keep the phone working fast?