Current Version: 1.0.1 available in cydia now
Supported iOS Versions: 4.0, 4.1, 4.2
Free trial for 5 days and beyond that a license is required at $2.99. Buy it now
Demo video on YouTube
Phone GV Extension is a system extension (NOT a standalone app) that seamlessly integrates Google Voice phone calling capability (both available GV dialing methods, Direct Dial mode and Call Back mode, are supported) into iPhone’s built-in Phone app. iOS 4.x (including 4.0, 4.1, and 4.2) are supported.
With the extension, phone calls routed through GV can be made directly from the built-in Phone app. Choose in 4 modes: GV Direct Dial, GV Call Back (in which if you use an a-list it won’t cost your minutes), Carrier, and Ask Before Dialing. It also provides a Dialing Rules Editor app to edit advanced dialing rules for per-number and/or prefix mode settings. Check pictures below.
Also, it provides the same calling experience as carrier calls in Phone app: the real recipient caller ID’s are displayed in dialing & in-call interface and in Call History instead of random GV #’s. You get a 100% native calling experience with your GV account. When a phone call is routed through GV a “GV Call” label is shown on the in-call interface. Press the “i” button to see detailed info.
Not gonna lie, this is the one app I would consider upgrading my 3GS to iOS 4.x for. I know he's planning on backporting to iOS 3.x but my impatience might get the better of me, heh.
I absolutely, ABSOLUTELY love this extension. Unfortunately, on my bill for last month I found some long distance charges for calls I made to Canada from the US that were supposed to have been made using Google Voice. I'm not sure how that happened, but from now on I am going to check for "GV Call" before allowing it to go through. Otherwise, this extension is a godsend!!
I have not had a problem with the GV Phone Extension not working properly in weeks. It now uses GV every single time, with no faults. Love this tweak!!!