ProtonMail, the iOS app that makes using PGP email a near-seamless experience, has now made itself even easier to use. Instead of having to use both your login and mailbox passwords, you can now use Touch ID to unlock encrypted mail. The app also offers support for password managers.
If you want to maximize security, you can set the app to require a PIN as well as your fingerprint, and can also make it auto-lock every time you exit the app – or after a preset time has elapsed.
Additional improvements include the ability to add attachments direct from cloud services (including iCloud), and to automatically display messages.
ProtonMail is a free download from iTunes.