As of today, the Threema apps are open source! To celebrate this occasion, the apps are available at half price until December 28. That’s 100% transparency at 50% of the price. Those who don’t use Threema yet have more compelling reasons than ever to regain privacy now.
Threema’s cryptographic procedures have been thoroughly documented from the outset, the proper application of the encryption library could always be verified independently, and external audits have repeatedly confirmed the apps’ security.
Now, we go a step further. To ensure full transparency and to dispel even the slightest shadow of a doubt, the Threema apps’ source code is publicly accessible starting today. It is subject to the AGPLv3 license, and thanks to reproducible builds, there’s a way to verify that the published code (of the Android app, for the time being) actually corresponds to the apps available for download.
Therefore, it’s no longer necessary to believe our claims or to trust someone else’s assessment. Anyone knowledgeable enough is now able to confirm Threema’s security on their own.
All information on how to download the source code, build it, and reproduce the app can be found here:threema.ch/open-source