You can visit ProtonMail on most Windows mobile devices, through an updated browser.
At this time Protonmail does not integrate with third party email clients on Windows due to the technology ProtonMail utilizes within web browsers to encrypt and decrypt your messages. We apologize for the inconvenience.
At this time ProtonMail is not building a Windows mobile application; however, we are planning on implementing a Windows application in the future. At this moment we are focusing on custom domains, threading, premium and business accounts, so we do not have an estimated date for the application.
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