aCalendar vs Etar
Price, platforms and features side by side. The table says where each price was read and when.
aCalendar
Android calendar with widgets, tasks and one-time upgrades
Where they differ
- aCalendar starts at $2.49 to $11.99 per one-time in-app upgrade; aCalendar+ is $11.99. Etar is free.
- aCalendar can be bought with a one-time purchase.
- Etar is open source, according to its own site.
- aCalendar also covers tasks.
At a glance
| aCalendar | Etar | |
|---|---|---|
| Pricing | Free plan | Free |
| Starts at | $2.49 to $11.99 per one-time in-app upgrade; aCalendar+ is $11.99 | Free |
| Free plan | Free version with ads: day, week, month, agenda and year views, 8 widgets, multi-select, printing and ICS or CSV export. Tasks, business features, public holidays and extra colors are paid upgrades. | Free and open source under the GPLv3. The app is installed from F-Droid or built from the source on GitHub, and the project lists no paid version. |
| Free trial | None listed | None listed |
| Android | ||
| Made by | Tapir Apps GmbH | The Etar Project |
| Price read from | play.google.com | github.com |
| Checked | Oct 9, 2026 | Oct 9, 2026 |
Who each one suits
aCalendar
- Android users who want a full calendar without a subscription
- People who want Google Tasks or Microsoft To Do lists inside their calendar
- Anyone who prefers to buy only the upgrades they need
Etar
- Android users who want a plain calendar with open source code
- People who sync a self-hosted CalDAV server through DAVx5
- Keeping an offline calendar that stays on the phone
Worth knowing
aCalendar
- Android only. The vendor states there is no iOS, web or PC version and that none is planned.
- The free version shows ads, and tasks, attendees, profiles, public holidays and the wider color choices all need a paid upgrade.
- In-app upgrades cannot be shared through Google Play Family Library; only the separate aCalendar+ app can.
- Licenses are tied to the store account and cannot be moved between Google Play and Huawei AppGallery.
Etar
- Android only; the F-Droid build of version 1.0.57 requires Android 6.0 or newer.
- No CalDAV client is included. Syncing a calendar with a server needs another app, such as DAVx5.
- The project describes its ICS import as unstable and advises caution if your provider sends invitation emails automatically.
- The Google Play link in the project's README returned a Not Found page on the check date; F-Droid carries the current version.
Key features
aCalendar
- Day, week, month, agenda and year views
- Swipe vertically to move through time and horizontally to switch views. Day and week views can show a mini month or a graphical week overview alongside.
- Eight home screen widgets
- Widgets include agenda, date, day and week layouts and a birthday widget added in version 2.9. Accent colors can be set per widget with the Colors upgrade.
- Tasks next to events
- The Tasks upgrade shows to-dos on their due dates in day, week and month views, with subtasks and a tasks widget. It works with Google Tasks, Microsoft To Do, CalDAV through Tasks.org, and local lists.
- Business features
- An upgrade adds attendee management, linking contacts to events, free or busy status, private events, and profiles that separate work and personal calendars.
- Print and export
- Calendar views can be printed or exported as PDF or PNG, and events exported as ICS or CSV files. Multi-select applies an action to several events at once.
- Uses Android's calendar sync
- The app runs no servers of its own. It reads and writes the calendars Android syncs, including Google Calendar, Microsoft Exchange accounts and CalDAV servers, plus local calendars.
Etar
- Month, week, day and agenda views
- Four views in a Material Design interface with dark and light themes. Recent versions let the week start on any day and can stagger overlapping events.
- Works with any Android calendar provider
- Etar reads Android's calendar storage, so it shows every calendar synced to the phone. You choose which ones are displayed and which one new events go to.
- Offline calendars
- A calendar can be created that is stored on the phone only and never synced to a server.
- ICS sharing, import and export
- Calendars can be shared as ICS files and imported or exported from storage, including invitations received by email. The project warns that import has known bugs.
- Agenda widget
- A home screen widget lists upcoming events in agenda form. The interface is translated into many languages by volunteers.
Plans
aCalendar
aCalendar$0
All calendar views, 8 widgets, flexible recurrences, birthdays, moon phases, printing and export. Shows ads, at most one a day according to the vendor.
In-app upgrades$2.49 - $11.99
one-time payment per item on Google Play
Ad-free, Tasks, Business Features, Colors and Holidays bought individually inside the free app. Not shareable through Family Library.
aCalendar+$11.99
one-time purchase on Google Play
A separate paid app with every upgrade included and no ads. It can be shared through Google Play Family Library.
Etar
Etar$0
The complete app, built and signed by F-Droid from the public source code. Version 1.0.57 requires Android 6.0 or newer.
Ways to pay less
aCalendar
- Other savings
Family Library sharing for aCalendar+
Bought as a paid app after July 2, 2016, aCalendar+ can be shared with up to 5 family members through Google Play Family Library. In-app upgrades are not eligible.
Etar
No public discounts listed.
