iOS Calendars

#1

Encrypted notes, tasks, calendar, files, passwords and a journal with mood and medication tracking, all unlocked by one 12-word recovery phrase. Sign up with no email and no password. Open source.

#2

Ad · Select the "Mail Plus" or "Proton Unlimited" paid plans for more features.

#3

Tuta: Free, Cross-Platform and Zero-Knowledge Calendar

#4

If you decide to self-host EteSync you won't have to pay for the subscription. Tutorial here .