The online payment option is particularly valuable for people with De-Googled devices, and on that topic Threema has been a champion of open source and free software ever since they open sourced their code in late 2020. You can also pay for a license via the website, using a masked payment option (such as a card or a prepaid gift card) and an alias or masked email address for near total anonymity. Instead, they assign you a randomly-generated username – a short, easy-to-share one, unlike some other messengers which can be just as easily shared as a QR code. You can sign up without ever entering any personal information, like a phone number or username. Finally, Threema offers a lot to their users in the way of privacy and anonymity.

They follow this up by having been audited by Cure53 – a well-reputed security company with a history of audits like this. Starting at the top, the company is based in Switzerland, which is well known for having strong consumer data privacy laws. Threema has a lot of strong attributes to like. For philosophical reasons, I think that everyone should use encryption whenever possible to normalize it and make mass surveillance less feasible/practical/economical. For practical reasons, it can protect sensitive communications like financial discussions, upcoming plans, and NSFW pics/texts if that’s your thing. I have long touted the need for E2EE in your daily communications for both practical and philosophical reasons.

Linux, Mac, Windows, and web clients also exist, but you’ll have to create an account on mobile first before connecting them (like Signal).

Threema is an end-to-end encrypted messenger available on Android, and iOS.

Threema vs signal