Contacts Sync for Gmail
Many of us store our contacts in multiple places. Having all your contacts synced up and with you on your iPhone could be a time saver. Contacts Sync for Gmail is an awesome application that syncs your Gmail and iPhone contacts and helps you get them more organized. It can also serve as a backup solution for iPhone contacts.
Contacts Sync offers 2 way syncing which merges the changes you have made to your iPhone and Gmail contacts. You could also do one-way syncing or go completely manual. Syncing can be filtered by groups. The main problem with some of these contact sync apps is that you end up with plenty of duplicate entries. This tool matches Gmail and iPhone contacts with the same name to prevent that from happening.
Contacts Sync can handle thousands of contacts in a flash. It syncs groups, labels, and photos. 4 delete modes are also provided for iPhone/Gmail contacts and groups. The user interface is not anything flashy but more than decent for what this tool offers.
Contacts Sync performed quite reliably in our tests. It does not crash and is very fast. Well worth trying if you need a tool to get your contacts organized.