It's official: WhatsApp shares the phone numbers of its users  with Facebook. This marks another significant diminishment of users'  privacy. Once again, the saying holds true: "If you're not paying for it, you're the product."

Is  there a way to opt out of this data sharing? No. While it seems to be  possible to prevent the use of said data for ad targeting on Facebook, "that data will still be shared", as TechCrunch points out.

Threema,  on the other hand, doesn't require users to provide their phone numbers  (or any other personal information, for that matter). Hence, it's  possible to use Threema completely anonymously.  If you do decide to synchronize your contacts, their phone numbers will  be transferred in hashed form and only matched while in volatile  memory, not stored. Data sharing is ruled out.

Due to its rigorous data restraint, Threema provides the highest level of privacy protection out of all popular mobile instant messengers. Decentralized management  of groups and contact lists, the option to use it anonymously, and  all-inclusive end-to-end encryption render Threema the best choice for  privacy-conscious users.

Many users seem to have recognized the signs of the times and are switching to Threema. Over the Weekend, the daily downloads of the Threema app have more than tripled (see chart).

Originally published at threema.ch.