As it becoming clear the more and more features it gets, the iPhone 3GS is basically a small computer that can fit in your palm or your pocket. And though it may not look like your desktop or laptop, sometimes it needs to be restarted just like those bigger machines.
The main reasons you'd need to reboot or Reset your iPhone 3GS are if a program crashes and locks up the entire phone or when the phone is running slowly or strangely (oftentimes, a restart will clear out whatever's gumming up the works).
To Reset the iPhone 3GS do the following:
- Hold down the home button (on the front of the phone) and the hold button (on the top right corner of the phone) at the same time.
- Don't let them go or else you'll take a screenshot.
- If the slider to turn the phone off appears, continue holding both buttons.
- After 10 seconds or so, the phone's should go dark.
- Then hold down the hold button at the top right until the Apple logo appears onscreen and the phone begins to boot up.
This process is related to the how you turn off the iPhone 3GS.

