What I do if it crashes?
Shoot me an email, but please understand that crashes are generic iPhone problems that can occur in any iPhone software, from Safari to Maps. While you’re working with an iPhone, iPod touch or iPad application the device may suddenly toss you back to the Home screen. When you return to the program, you may further find that some of your recent changes have been lost. After being dumped back Home, you should simply return to what you were doing and hope the crash does not recur. If the same crash does happen again, try restarting your iPhone (described next). This often helps because many crashes are caused by a combination of events that won’t reoccur in exactly the same way after a restart.
To restart an iPhone, press and hold the Sleep/Wake button (the physical button at the top of the iPhone until a red (and white arrow) slider (adjacent to the words “slide to power off”) appears on the screen. Drag the slider to power off your device. Then press and hold the Sleep/Wake button again until the Apple logo appears. Wait a few seconds for iPhone’s startup sequence to finish, and you should be back at the Home screen. While I refer to this procedure as a “restart,” some Apple documentation refers to it as a “reset.” I prefer “restart” both because it is consistent with the same action on a computer and because it avoids confusion with other meanings of “reset” for the iPhone.
If your device is really confused, even holding down the Sleep/Wake button may have no effect. In such cases, you can generally force the iPhone to restart by holding down the Sleep/Wake and Home buttons simultaneously for around 10 seconds. Although I have no official confirmation of this from Apple, I expect that the difference between a normal and a forced restart is that the former restart is more “graceful,” making sure that all files that should be closed before restarting have done so.