Teffel is an exciting mutual phone contact detector app which can be used to filter out your mutual contacts between you and some other individual using it. It can be used for fun and enhancing communication with people.

Functionality:
-User needs to register first ,providing his contact number twice one of them consisting of country code and one without it + name and password .
-Then a user is supposed to login providing same credentials.
-Teffel Syncs your phone contacts into the app.

Enable your friend/family member to install this app and follow the same procedure and you both should be able to see your mutual contacts in the app if they exist.