Although Apple has once again bowed to AT&T corporate pressure and banned Google Voice and all related apps from the App Store, you can still harness the power of Google Voice for your iPhone.
Go to Cydia – a kind of “grey” app store for iPhone – and get GV Mobile. It’s free on Cydia, and it optimizes Google Voice for the iPhone. This is where I picked up my version of GV Mobile, and I’m loving Google Voice. It’s a powerful communication tool that takes advantage of the power of a smart phone.