i am having a freezing problem with my iPhone. it started about a week ago. what happens is sometimes when i push the button to take it out of sleep mode it will just be a black screen for a few seconds then the slide to unlock screen will appear. and sometimes when i slide to unlock the screen stays black and i have to put it to sleep and then do it over for me to see the menu. and today i took out of sleep unlocked it and then tried to use the calculator but nothing on the homescreen worked. i pushed every menu item and nothing happened. i turned the iPhone off then back on and it is fine now but idk what is happening. should i be concerned as to bringing it to Apple or wait for an update?