Unless you’re using over-the-air Microsoft Exchange syncing with your iPhone (via Google Mobile Sync, NuevaSync or a corporate Exchange server), you’re probably keeping its contact and calendar information in sync with Outlook or iCal using iTunes.
This works well enough, but what if your calendar and contact data is stored one computer (at the office, say) and your iTunes library is stored on another (maybe at home)? Try plugging the iPhone into both and you’ll quickly discover that iTunes is fond of erasing the data put in place by the other iTunes on every sync.
Fortunately, you can successfully synchronise an iPhone or iPod Touch with iTunes on two separate computers — here’s how. (more…)