As TechCrunch notes, it took 16 months, but a Google Voice app has finally made its way to the iPhone:
The official Google Voice for the iPhone is here. And it’s wonderful. Yes, it was even worth that insane wait.
So what's so great about Google Voice?
If you’ve used Google Voice on your computer or other devices, the iPhone version should be familiar to you. However, unlike the Android version, Google Voice cannot totally take over the calling capabilities on the iPhone. All that means is that you have to open the app instead of your regular iPhone Phone app to use it.
But you can make calls right from the app. You dial a number and it automatically takes you to the iPhone’s Phone app where it places the call from your Google Voice number by way of Google’s backend system.
When you receive a call to your Google Voice number, it will come in to your regular Phone app as well, just as happens now with call forwarding.
You can also send and receive texts from the app. And you can listen to your Google Voice voicemails — and yes, all of them are transcribed for you to read in the app. And all of this works with the iPhone’s Push Notification system.
And unlike the HTML5 version, the native app can access your phone’s contact list. This make it easy to place calls and set up Quick Dial Contacts.