I’ve been using Proton Unlimited for a few years and I’m planning to switch to Fastmail soon.
Mostly because I dislike Proton not supporting the standard client protocols. I know Proton’s “zero-knowledge encryption” is the reason why, but that doesn’t feel like the most meaningful privacy gain to me considering it’s only for the message body and doesn’t apply to email metadata. Proton could try collaborating with and extending open standards with the encryption features they need, making it feasible for third-party clients to implement sync without a bridge, but they haven’t.
Needing a mail bridge is a moderate annoyance on desktop. But on mobile it means you’re basically forced to use their app. At least the Proton Android app is GPL and I haven’t had issues with it, but I don’t like the lock-in existing at all. Fastmail in contrast has been pushing forward JMAP as an open standard to make mobile sync on third-party clients better than what’s possible in IMAP.
I also don’t like Proton Unlimited being limited to 3 domains and 15 total addresses (not counting simplelogin). Fastmail has far higher limits there.
Both services seem to use a fair bit of proprietary software server-side but I think Fastmail has more of the important stuff be FOSS including their main imap/caldav/etc server (Cyrus).
I’ve been using Proton Unlimited for a few years and I’m planning to switch to Fastmail soon.
Mostly because I dislike Proton not supporting the standard client protocols. I know Proton’s “zero-knowledge encryption” is the reason why, but that doesn’t feel like the most meaningful privacy gain to me considering it’s only for the message body and doesn’t apply to email metadata. Proton could try collaborating with and extending open standards with the encryption features they need, making it feasible for third-party clients to implement sync without a bridge, but they haven’t.
Needing a mail bridge is a moderate annoyance on desktop. But on mobile it means you’re basically forced to use their app. At least the Proton Android app is GPL and I haven’t had issues with it, but I don’t like the lock-in existing at all. Fastmail in contrast has been pushing forward JMAP as an open standard to make mobile sync on third-party clients better than what’s possible in IMAP.
I also don’t like Proton Unlimited being limited to 3 domains and 15 total addresses (not counting simplelogin). Fastmail has far higher limits there.
Both services seem to use a fair bit of proprietary software server-side but I think Fastmail has more of the important stuff be FOSS including their main imap/caldav/etc server (Cyrus).