If you want to setup Gmail on the iPad so you could access Gmail when you are away from my desktop or on the road. Benefits over the generic Gmail set are as follows; your iPad will now store Drafts and Sent Mail in Gmail instead of storing them locally on the Device. That way if you access Gmail from your desktop or iPhone your drafts and trash will be accessible on that device. This method will also work with the iPhone.
Seems that the powers that be over at Apple have pulled all Google Voice-enabled applications from the App Store, citing the fact that they “duplicate features that come with the iPhone”.