Why does my phone switches off by it's self and just displays appl ico
my iPhone just switches off on it's own and just displays the apple icon for hours without turning on.
Try pressing and holding up to 10-15 seconds both the power and home buttons at the same time. If the Apple logo is on or flashing this should turn it off. Do it again to start the phone up.
If you get a picture of a lightning cable pointing at an iTunes icon you need to plug your phone into a computer that has iTunes already open. Make sure you have the latest versions of iOS and iTunes. Use a good Apple USB cable. Then follow directions to first try Updating the iOS software if that fails you will be told to Restore your phone which will wipe out your personal settings and data. Of course you have a backup you can then restore from iCloud or your computer, right? You can use the backup to reload all of your personal stuff.
Hope this solves your problem!