The application has both black list functionality for rejecting calls, and whitelist functionality to accept-only list of numbers. CallGuard mutes, rejects your incoming calls and sends the SMS message to the contact number, who was calling you. Now there is no need to mute the phone, if you have a meeting and are waiting for the important call. You need to create the white list and all the calls except the listed one will be muted or rejected according to your settings.
