O-Sync is a free online backup and synchronization service for mobile phones that support SyncML protocol.
O-Sync supports synchronization of calendar, contacts, tasks and notes (for supported devices). Once all your mobile data has been synchronized online, you can access your contacts, calendar and tasks through an online web interface and view, add, modify and delete entries.

Other features include:

*Add photos to contacts.
*You can invite contacts to your O-Sync network. If a contact is in your O-Sync network, any change that the contact makes to his personal information automatically gets updated into your account and synchronized to your mobile phone (similiar to Plaxo).
*If you format your phone, all you need to do is sync with O-Sync and all information is pushed to your mobile device.