Tuta
More and more exciting reviews about Tutanota are popping up online: "Given that Tutanota is open source, and they have a pipeline of amazing products in development, I pulled the trigger and moved my email there." 😁 We're always happy to hear what our users think, let us know so we can add your review here:
https://tutanota.com/blog/posts/tutanota-secure-email-review
Tutanota email reviews - updated.

Tutanota is one of the most secure email services due to its focus on encryption and open source. Check out these reviews.

Apr 4, 2019 at 8:35amWeb
Show threadQuad 🌸Apr 4, 2019
@Tutanota I moved to Tutanota along with both my domains last week and it's been working great so far. Really like it, you did a good job setting up a user-friendly encrypted mail service.
Show threadTutaApr 4, 2019
@quad Thanks for your feedback, that's good to hear! 
Show threadDationeApr 4, 2019
@Tutanota
I feel very strange every time you say "Tutanota is open source" because my brain immediately adds "only on the client side". Are you doing that on purpose?
Show threadTutaApr 4, 2019
@datione Of course, it's the client-side - which handles the entire encryption - we never said anything else. Though we plan to build a small open sourced server (not as complex as the one we are using) that people will be able to host locally. But this is a lot of work, and a bit further down the development road. Thanks for your patience!