More Privacy when Using WhatsApp, Signal and Co

This is how the planned ContactGuard integration in the address book application could look like: Activating a 'sensitive contact' function denies messenger services and third-party providers access to the data. Lunghammer - TU Graz/TU Darmstadt - Cryptography experts at TU Graz, together with their colleagues at TU Darmstadt, have developed a privacy-protecting security software for mobile messaging services. When installing a messaging service on a smartphone, users are usually prompted to give the app access to their own phone address book. This will automatically connect them with those contacts from their address book who already use the messaging service. For this purpose, the service provider matches the telephone address books with its own contact database. This process currently uploads the complete address books to the service provider's servers. This so-called "mobile contact discovery" process constitutes a massive invasion of privacy.