Originally Posted by
gfunkdave
No, this is an "end to end direct dial" application. If I select "Use Google Voice for all calls", then any time I call someone, it makes the call through Google Voice. My phone actually dials some access number, but it's seamless and just as quick as dialing regularly.
I also have the option to never use Google Voice, to use Google Voice only for international calls, or to ask me every time.
Voicemail and forwarding options are separate.
That's not truly end-to-end. It initiates a regular phone network call, then joins the calls based on your outbound call. So it still uses minutes technically. It feels end-to-end but it's hacky since it uses the phone network.
Sipdroid is 100% over wifi or 3G DATA only. Trust me. I use this daily in the UK w/o using any minutes whatsoever.