We are happy to inform you that we have started to build desktop applications for OS X, Linux and Windows. Desktop clients will enable you to import emails to your encrypted Tutanota mailbox as well as give you offline access. Building desktop clients is an extensive project, so we cannot give an exact ETA.
If you would like to support our development team, please donate to Tutanota: https://tutanota.com/community#donate
We use this money to further grow our development team and speed up our development: https://tutanota.com/blog/posts/welcome-ivan
Thank you very much for your support!
Your Tutanota TeamRasmus Havhus commented
PGP in Apple Mail... well, I never felt comfortable with it. Too much to trust, and no visibility in the user interface.
Since Im safekeeping minimum 10 years of mail on my laptop (OSX) I would want everything to be importable, as I cannot handle 2 mail apps, meaning remember where a conversation took place.