Google has updated the iOS Google Voice app to include support for the iPod touch and iPad…See Detatils
@TatWza

You can use the app to initiate GVoice calls with a nearby phone. The process is known as Click2Call, users click any ‘Call’ button within the app and then choose which of their phones they want to ring. The app now disables text forwarding when you enable Push Notifications (to avoid double alerts), and there’s a new Do Not Disturb option in the Settings tab for those who’d prefer to disconnect.

iTunes