Which service offers the best security for email: ProtonMail or Tutanota?

ProtonMail:

Protonmail, the largest encrypted email service in the world

Proton Technologies AG is a security company headquartered in Geneva, Switzerland, near CERN where the founders met in 2013.
We are researchers, scientists, and engineers brought together by a shared vision of protecting civil liberties, working to advance Internet security and privacy. Proton Technologies is a uniquely community-driven company.
Initial funding came from an online crowdfunding campaign that raised $550,000 and set a record for a software technology project.
Today, the innovative technologies that we are developing, such as ProtonMail and ProtonVPN, are used by millions of people around the world.

link : https://protonmail.com

Tutanota:

Tutanota is a German webmail service that was created following the revelations of Snowden and encrypts emails end to end (and locally in the browser) both between users of the service that external users.

Indeed, if you send an email to a poor guy who's in Gmail and that sucked the least of his thoughts by the NSA, you can specify a password that you provide directly (via a secure channel) and it will read your message directly to the Tutanota site by entering the password.

Please note, I said something anyway. Tutanota has no basic password or your messages in the clear.
The whole process encryption / decryption password via browsers.
So, if you forget your password Tutanota, well you have it in the ass.

This service was developed by 3 former computer students become experts in encryption and currently they bossent on the development of a mobile application.

Tutanota in its free version offers 1 GB of storage and the source code is already available .
Then in a few months, it will be packaged for you yourself create your own clone Tutanota just for you. Very cool !

I tested and it made me look pretty damn good. With you to test now .

Link : https://tutanota.com/index