Fossify Calendar vs Tuta Calendar
We give Fossify Calendar a 3.0 GPA and Tuta Calendar a 3.2, out of 4.0. Fossify Calendar grades higher on the free plan. Tuta Calendar grades higher on platforms. They get the same grade on value for money, features and ease of use.
Price, platforms and features side by side. The table says where each price was read and when.
Fossify Calendar
Open-source Android calendar with no ads, tracking or account
Tuta Calendar
End-to-end encrypted calendar bundled with Tuta Mail
How we grade them
| 3.0GPAFossify CalendarVery good | 3.2GPATuta CalendarVery good | |
|---|---|---|
| Value for money | AIt costs nothing. The complete app is free on Google Play and F-Droid with no in-app purchases, and the project lives on optional donations. | ATuta's lowest paid personal plan is €3 a month paid yearly, €3.60 monthly, taxes included. That's under what most calendar apps charge, and it's Tuta's encrypted email, unlimited calendars and 20 GB of storage in one. The calendar isn't sold on its own. |
| Free plan and trial | AFree and open source under GPL-3.0, with no ads, no tracking, no account and no paid tier holding anything back. You get all of it from day one. | BThe Free plan gives you one encrypted calendar and 1 GB, with apps on every platform. But there's no calendar sharing, no event invitations and no offline support, so it's a calendar for you alone. Those limits are tight. |
| Features | BDay, week, month, year and event-list views, repeat rules, reminders with custom sounds, file import and export, and birthdays pulled from your contacts. Solid basics. But there's no sync service of its own, so that depends on what's on your phone. | BEnd-to-end encryption on events, invitations and shared calendars, with reminders kept hidden from your phone's operating system. On paid plans you can share with read or write rights. But the calendar page mentions no two-way sync with Google or Outlook, only import. |
| Ease of use | BThere's no App Store rating to go on, as it isn't on iPhone. Install it and it works, with no sign-up. If you want syncing, the Google, Outlook, Nextcloud or Exchange account has to be set up on the device already. | BIt's part of your Tuta account, so if you use Tuta Mail it's already there, and old calendars import in the settings. We have no App Store rating on record to go by, so it stops at a B. |
| Platforms and integrations | DAndroid only. The Fossify project lists Android as its sole platform. It syncs through accounts already on the phone, such as Google Calendar, Outlook, Nextcloud or Exchange. | BIt runs on everything: web, Windows, macOS, Linux, iPhone and Android, with the Android app on F-Droid too. But the only thing it connects to is Tuta Mail, and no API is listed. That keeps it at a B. |
| Best for | a private Android calendar with no ads | a calendar your provider can't read |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: Fossify Calendar and Tuta Calendar. How we grade
Where they differ
- Fossify Calendar is free. Tuta Calendar starts at €3 per month, paid yearly (€3.60 paid monthly).
- Only Tuta Calendar lists a web app.
- Only Tuta Calendar lists macOS, Windows, Linux and iOS apps.
- Tuta Calendar is end-to-end encrypted, according to its own site.
At a glance
| Fossify Calendar | Tuta Calendar | |
|---|---|---|
| Pricing | Free | Free plan |
| Starts at | Free | €3 per month, paid yearly (€3.60 paid monthly) |
| Free plan | Free and open source under the GPL-3.0 license, with no ads, tracking or account. The project takes donations through GitHub Sponsors, Patreon, PayPal, Liberapay and Open Collective. | One encrypted calendar and 1 GB of storage, with web, mobile and desktop apps. No calendar sharing, event invitations or offline support. |
| Free trial | None listed | None listed |
| Web | ||
| macOS | ||
| Windows | ||
| Linux | ||
| iOS | ||
| Android | ||
| Made by | Fossify | Tutao GmbH |
| Price read from | play.google.com | tuta.com |
| Checked | Oct 9, 2026 | Oct 5, 2026 |
Who each one suits
Fossify Calendar
- Android users who want a calendar without ads, tracking or sign-up
- People who prefer open-source apps installed from F-Droid
- Keeping a private, local calendar that never leaves the phone
Tuta Calendar
- People who want a calendar their provider cannot read
- Tuta Mail users who want email, contacts and calendar in one account
- Linux users looking for an open-source desktop calendar client
Worth knowing
Fossify Calendar
- Android only; the Fossify project lists Android as its sole platform.
- The app has no sync service or cloud account of its own. Syncing depends on accounts or calendar providers configured on the device.
- Development is funded by donations, and help comes through a public issue tracker and community channels.
- Google Play and F-Droid publish releases on their own schedules, so versions can differ between stores.
Tuta Calendar
- The Free plan includes one calendar and has no calendar sharing, event invitations or offline support.
- Calendar has no subscription of its own: paid features come with Tuta's paid personal or business mail plans.
- Prices are listed in euros: personal plans include taxes, business plans exclude them, and totals can vary with payment platform fees and exchange rates.
- Other calendars are brought in by import; the calendar page mentions no two-way sync with Google or Outlook calendars.
Key features
Fossify Calendar
- Five calendar views
- Day, week, month, year and event-list views, with event filters to narrow what is shown and controls for color, theme and display.
- Recurring events and reminders
- Events take times, durations, reminders and advanced repetition rules. Reminder sounds, looping audio and vibration can be customized.
- Sync through device accounts
- Calendar data can sync through accounts or calendar providers set up on the device, such as Google Calendar, Outlook, Nextcloud or Exchange. Fossify runs no sync service of its own.
- Import and export
- Calendars can be imported from and exported to files, which keeps the data portable and gives a way to back it up or move it to another app.
- Holidays, birthdays and anniversaries
- Holidays can be imported, and birthdays and anniversaries can be drawn from the phone's contacts if contacts access is granted.
- No Internet permission
- The app does not request Android's Internet permission, contains no advertising and sends no app data or usage records to Fossify.
Tuta Calendar
- End-to-end encryption
- Events, invitations and shared calendars are encrypted end to end with what Tuta calls quantum-safe encryption, so the provider cannot read them.
- Encrypted reminders
- Event reminders arrive as push notifications on phones and computers. They are sent encrypted and kept hidden from the phone's operating system.
- Calendar sharing
- On paid plans a calendar can be shared with family or colleagues with read only, read and write, or write and manage sharing rights.
- Event invitations
- Paid plans can send and receive calendar invitations, and can send one encrypted to someone outside Tuta using a shared password.
- Apps on every platform
- Apps for Android and iPhone, open-source desktop clients for Windows, macOS and Linux, and a browser version. The Android app is also offered through F-Droid.
- Built into Tuta Mail
- The calendar shares an account with Tuta's encrypted email and contacts, and existing calendars can be imported in the settings.
Plans
Fossify Calendar
Fossify Calendar$0
The complete app, installed from Google Play or F-Droid, with no ads or in-app purchases. Donations are optional.
Tuta Calendar
Free€0
One encrypted calendar, 1 GB of storage and apps on every platform. No calendar sharing or event invitations.
Revolutionary€3
per month, paid yearly (€3.60 paid monthly), incl. taxes
Tuta's personal mail and calendar plan: unlimited calendars, calendar sharing, event invitations, offline support and 20 GB of storage.
Legend€8
per month, paid yearly (€9.60 paid monthly), incl. taxes
The same calendar features with 500 GB of storage, 30 extra email addresses, 10 custom domains and priority email support.
Essential€6
per user / month, paid yearly (€7.20 paid monthly), excl. taxes
Business plan with unlimited calendars, sharing and event invitations, shared mailboxes and 50 GB of storage per user.
Advanced€8
per user / month, paid yearly (€9.60 paid monthly), excl. taxes
Business plan with the same calendar features, 500 GB of storage per user, 10 custom domains and priority email support.
Unlimited€12
per user / month, paid yearly (€14.40 paid monthly), excl. taxes
Business plan with 1,000 GB of storage per user, unlimited custom domains and custom branding.
Ways to pay less
Fossify Calendar
No public discounts listed.
Tuta Calendar
- Annual discount
Pay yearly and save two months
Tuta's pricing page shows a yearly payment saving €7.20 on the lowest paid plan (€36 instead of €43.20) and €19.20 on Legend (€96 instead of €115.20).
- Nonprofit
50% off for nonprofits and schools
Registered nonprofits and schools for general education can apply to Tuta's sales team for a 50% discount on a subscription.
- Other savings
Free for qualifying open source projects
Open source teams can apply by email for a free version of Tuta. Tuta's blog sets out which projects qualify.
