contacts, mobile-phones, simI have backed up my contacts to another SIM, but that doesn't retain extra data such as multiple numbers or address data. I'm looking for a service that will allow me to backup the contact data in a form that is independent of operator and handset manufacturer. Do any such services exist?
Depends on your phone but I live by Google Sync
All Android phones do this natively.
Check out Lookout and their app for Android. Its free. It lets you backup pictures + contacts + other stuff. You can even initiate a backup remotely!
In addition, also has a remote locator for your phone. (no remote wipe yet)
If your goal is just to backup Contacts, as long as you use the Android "Contacts" app (and not the app that came from the phone manufactures), its always backed up to your google account, so technically you do not need to back it up.
All content is licensed under CC BY-SA 3.0.