Android - supress the native In Call Screen and replace with 3rd party?

Currently creating a VOIP application for Androi开发者_运维技巧d and I was wondering is there any possible way to supress the In Call Dialog when sending a call over GSM and use our own 3rd party In Call Dialog or screen instead?

At the minute when we switch from our VOIP call and send it over GSM via the ACTION_CALL intent it does everything we want except it brings up the native In Call screen whereas we want our own In Call screen to display here.

So I was wondering what kind of options we would have on this?

What would you reccomend we look into doing?

Thanks in advance

Unless you are running your app on a rooted device, you cannot supress the native in call screen, nor the native calling screen.