The ProtonMail Bridge is an application that runs on your computer in the background and seamlessly encrypts and decrypts your mail as it enters and leaves your computer. It allows for full integration of your ProtonMail account with any third party client that supports IMAP and SMTP such as Microsoft Outlook, Mozilla Thunderbird and Apple Mail. This includes support for importing emails into your ProtonMail account from other email accounts that are connected to the same client, as well as full-text search of your ProtonMail emails from within your client.
Currently, versions for macOS and Windows are available at the ProtonMail Bridge homepage, along with frequently asked questions and detailed setup instructions for each of the supported clients. The Bridge release for Linux, which will include a command-line interface version, is currently in development.
The ProtonMail Bridge software is currently only available for paid ProtonMail users, although this may change in the future if we have the infrastructure to support free users as well.
For easier access on mobile devices we developed applications for iOS and Android. You can download them using the Market Store on your mobile device (App Store for iOS and Google Play Store for Android).
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