Privacy: Encrypted Email

Criteria CTemplar ProtonMail Tutanota
Audited? Yes Yes Web client only
Available on Debian? Yes No Yes
Available on Mac? Yes No Yes
Available on Windows? Yes No Yes
Available on Android? Yes Yes Yes
Available in F-Droid (Android Only)? Yes No Yes
Available on iOS? Yes Yes Yes
Based in 5/9/14 Eyes? No No Yes
Free plan available? Yes Yes Yes
PGP-Based Yes Yes No
Additional notes? No independent backup solution Includes VPN service with all plans