Reboot your iPhone.

That’s it. Just reboot it. Hold the Sleep/Wake Button at the top right-hand corner of the iPhone for a few seconds and run the slider across the screen when it asks. When your iPhone shuts down, wait a few seconds and press the Sleep/Wake button to power it back up again. This will fix so many problems preemptively.

Reboot your iPhone when normally rock-solid apps start crashing. You should really do this every couple of days to keep those rock-solid apps from crashing and to minimize the funkiness of the less-than-solid apps.

If you’re like me, sometimes you’ll go for weeks without rebooting your iPhone. For the most part, my iPhone just works and it’s easy not to think about rebooting on a regular basis. It’s one of the reasons we love Apple products.

It’s easy to forget that inside it’s a computer and that as you use it — opening and quitting apps — its runtime free memory (RAM) can become fragmented over time. Rebooting your iPhone flushes the memory and the fragmentation. Suddenly, your apps have 40 MBs to play with (on a 2G or a 3G) — a lot more on a 3GS.

When I did Mac desktop support, rebooting the computer fixed about half the problems. Seriously. Your iPhone is a computer. To help keep it running smooth, rebooting should be an easy part of your iPhone’s regular maintenance.