Our ProtonMail Android app is now open source! Starting today, every app you use to access Proton services are open source and have passed an independent security audit. You can find all the details here. https://protonmail.com/blog/android-open-source/
The ProtonMail Android app is open source

Our ProtonMail Android app is open source. This is part of our commitment to transparency and to contributing to the open source and privacy tech community.

ProtonMail Blog
@protonmail Great news, thanks for your efforts! I also add to the people who are requesting this: do you intend to make it available thorugh @fdroidorg? That would make a lot of sense for people using an Android without Google Apps, and using such Android makes a lot of sense for people concerned with privacy, which is probably the kind of people who use Proton Mail and services 😉