Site's still lacking some details, but as far as I understand:
- really good SSL grade (A+, see [1])
- SSL only
- HSTS to prevent http connections
- You can select to send from your 'secure.mailbox.org' alias, which seems to enforce TLS for smtp (and WILL break if the recipient doesn't support it, they explicitly want that)
- You can enable DANE, enforce DANE, require that the server already knows the certificate of your target domain
- They have 'easy' explanations on how to use PGP
- There's an option to encrypt your whole mailbox on the server ('neither the police nor we can read your mails'), but I couldn't find details about that
Note: Not affiliated, not a customer, merely reading the site myself and German's my native language.
About PGP encryption. You can enable Inbox Encryption in the settings. You enable it and paste your public PGP key in as well, and all incoming emails that are not encrypted will be encrypted using your public key.
You can also force the use of SSL/TSL for all emails in the settings, so that you do not have to use the "special" address for that.
- really good SSL grade (A+, see [1])
- SSL only
- HSTS to prevent http connections
- You can select to send from your 'secure.mailbox.org' alias, which seems to enforce TLS for smtp (and WILL break if the recipient doesn't support it, they explicitly want that)
- You can enable DANE, enforce DANE, require that the server already knows the certificate of your target domain
- They have 'easy' explanations on how to use PGP
- There's an option to encrypt your whole mailbox on the server ('neither the police nor we can read your mails'), but I couldn't find details about that
Note: Not affiliated, not a customer, merely reading the site myself and German's my native language.
1: https://www.ssllabs.com/ssltest/analyze.html?d=mailbox.org