Proton Mail for Android

Copyright (c) 2026 Proton Technologies AG

Contributing

We’ve recently rebuilt the app and are focused on our current roadmap of features and fixes. Therefore, we are not accepting new issues or PRs at the moment: feel free to fork the repo for your own experiments. We appreciate your understanding and support.

Build instructions

• Install and configure the environment (two options available)
  • Android Studio bundle
  • Standalone Android tools
• Install and configure Java 17+ (not needed for Android Studio bundle as it's included)
  • Install Java 17 with brew install openjdk@17 | apt install openjdk-17-jdk
  • Set Java 17 as the current version by using the JAVA_HOME environment variable
• Clone this repository (Use git clone git@github.com:ProtonMail/android-mail.git.)
• Ensure Git LFS is installed (git lfs install) for snapshot test assets
• Setup google-services.json file by running ./scripts/setup_google_services.sh
• Build with any of the following:
  • Execute ./gradlew assembleAlphaDebug in a terminal
  • Open Android Studio and build the :app module

CI / CD

CI stages are defined in the .gitlab-ci.yml file and we rely on fastlane to implement most of them. Fastlane can be installed and used locally by performing

bundle install

(requires Ruby and bundler to be available locally)

bundle exec fastlane lanes

will show all the possible actions that are available.

Deploy

Each merge to main branch builds the branch's HEAD and deploys it to Firebase App Distribution.

Observability

We use Sentry for crash/error reporting (primarily for non-debuggable builds).

• Runtime crash/error reporting: the DSN is injected at build time via environment variables (SENTRY_DSN_MAIL and SENTRY_DSN_ACCOUNT). If these variables are not set (typical for local builds and forks), Sentry is effectively disabled.
• Mapping/symbol uploads (CI / release tasks): CI provides a sentry.properties file for uploading ProGuard/R8 mappings and native symbols.

Code style

This project's code style and formatting is checked by detekt. The rule set is ktlint's default one.

License

The code and data files in this distribution are licensed under the terms of the GPLv3 as published by the Free Software Foundation. See the GPLv3 license text for a copy of this license.