Power Off and Restart

• The quickest and simplest way to correct a software glitch is to shut the iPhone off. To do so, press and hold the "Sleep/Wake" button until the red power-slider appears at the top of the screen. Slide the button to power the phone off, wait 30 seconds and then press the "Sleep/Wake" button to turn on the phone. If this does not help, restart the phone by pressing the "Sleep/Wake" and "Home" buttons simultaneously for 10 seconds until the Apple logo appears. Repeat this process if your first attempt does not work.
  
  

Update

• Not having the latest software updates or installing them incorrectly can cause incompatibility issues or glitches, according to Apple Support. Connect your iPhone to your computer, open iTunes and click your iPhone's name under "Devices" in the left column. In the Summary page that appears, click "Check for Updates." Download any available updates, leaving your iPhone plugged in and untouched until the software is fully installed.
  
  

Restore

• If all else fails, restore your iPhone to factory settings, which completely wipes the iPhone's hard drive and reinstalls the basic software. You can immediately re-sync all of your media from iTunes, but you lose your personal settings and data when you run the restore option. To restore, attach your iPhone to your computer. Open iTunes and click the "Restore" button on the Summary page of iTunes below "Check for Updates." Follow the prompts in the dialog box that appears. Choose to restore from a previous backup -- one you made before you started having this glitch -- or choose to set up the phone as a new device.
  
  

Hardware Malfunctions

• Occasionally, you may experience a glitch caused by internal hardware damage. Exposure to liquids or extreme temperatures can cause the circuit boards and wires to melt, corrode or short. Dropping the phone can also break your internal hardware. If this is the case, you will not be able to repair the phone yourself, but an Apple technician may be able to fix or replace the phone. However, liquid damage is generally not covered under your warranty.