Flip

This service allows you to mute incoming call on your phone.
Just put the phone screen down to silence it.

The main feature that service is not too sensitive, so you shouldn't take care about angle too much.

English, Russian, French and Ukrainian languages are supported.

This app won't suck up your battery, as many other similar apps would do, so it is the right choice for those who don't want to stuck in the middle of nowhere with dead phone :)

Just try it for free.