A bit late, but an important event of 2019 that was not covered here. CERN recently opened source the ProtonMail app for iOS. ProtonMail is a secure email with PGP encryption based on elliptic curve.
Previously, CERN opened the source of the web interface, OpenPGPjs and GopenPGP libraries, and also conducted an independent annual code audit for these libraries.
In the near future, the main priority is to open the source of the application for Android. Responding to user comments, one of the developers of the company, Ben Wolford, said: “After the application passes an independent audit, the source code for the Android client will be publicly available.”
This is a top priority for us. As soon as the audit is complete, we will open source the Android app.
Source: linux.org.ru