Secure, private and end-to-end encrypted calendar, contacts and tasks sync
About this app
Secure, end-to-end encrypted, and privacy respecting sync for your contacts, calendars, and tasks (using Tasks.org and OpenTasks). For notes, please use the EteSync Notes application.
In order to use this application you need to have an account with EteSync (paid hosting), or run your own instance (free and open source). Check out https://www.etesync.com/ for more information.
Easy to Use =========== EteSync is very easy to use. It seamlessly integrates with Android so you won't even notice you are using it. Security doesn't always have to come at a cost.
Secure & Open ============ Thanks to zero-knowledge end-to-end encryption, not even we can see your data. Don't believe us? You shouldn't, just verify yourself, both the client and server are open source.
Full History ========= A full history of your data is saved in an encrypted tamper-proof journal which means you can review, replay and revert any changes you have made at any point in time.
How does it work? =============== EteSync integrates seamlessly with your existing apps. All you need to do is sign up (or run your own instance), install the app, and enter your password. After that, you will be able to save your contacts, calendar events and tasks to EteSync using your existing Android apps, and EteSync will transparently encrypt your data and update the change journal in the background. More security, same work-flow.
Licensed under GPL-3.0-only.
What's New in v2.7.0
Imported from the F-Droid repository index.
Version history
Mar 9, 2026 · 11.2 MB · Android API 21–36 · code 20700
Imported from the F-Droid repository index.
SHA-256 1ba72af98c30a790a5925f4e59493922efd7109e3b2bffe6510fb6b6671d7be8
Oct 23, 2025 · 11.2 MB · Android API 21–36 · code 20600
Imported from the F-Droid repository index.
SHA-256 f92a3bdb3ef79108edb8b105748787d899a363936bfc022b8b64eaa6cf22ec98
Mar 9, 2024 · 11.3 MB · Android API 21–33 · code 20404
Imported from the F-Droid repository index.
SHA-256 a84a94bd17857b430095e0e60af67c2bc7909ad1a169703bdf28fc38e9b5a57e
Will it run on your device?
92%
- Runs on a broad range of modern Android versions.
- Multiple CPU architectures are covered.
- Aligned with the latest Android target SDK expectations.
Installation Guide
Open Settings on your Android device
Go to Security → Unknown sources (or Install unknown apps)
Enable "Allow from this source" for your browser or file manager
Open the downloaded APK file from your Downloads folder
Tap "Install" and wait for installation to complete
Launch the app from your home screen
Make sure to re-enable Unknown Sources restrictions after installation for security.
How to install this safely
How to verify the file you downloaded
Before you install anything, confirm the file is the one described here. On a computer, run shasum -a 256 your-download.apk (macOS or Linux) or certutil -hashfile your-download.apk SHA256 (Windows), then compare the output character-for-character with the SHA-256 on this page. If a single character differs, the file is not the build we recorded — delete it.
What the signing certificate proves
Every Android app is signed with a private key that only its developer holds. The fingerprint on this page is a hash of the matching public certificate, and it proves continuity rather than identity: it tells you a build came from whoever signed the earlier ones. Android enforces this at install time — if a package claiming to be com.etesync.syncadapter is signed with a different key, the system will refuse to install it over your existing copy. A fingerprint that changes between releases is worth pausing on, because a repackaged app that has been modified by someone else cannot keep the original signature.
How to roll back to an earlier version
If the current release misbehaves, 2.6.0 is the last build before it. Android will not install an older version code over a newer one, so you must uninstall EteSync - Secure Data Sync first — which clears its local data unless you have a backup. Reinstall the older APK only if its signing fingerprint matches the build you already trust, and check the API range: an older release may target an Android version your device has moved past.
Why we list sources instead of hosting everything
The official store channel is almost always the right choice: it updates automatically and carries the publisher's own distribution guarantees. A direct APK is useful when a device has no store access, when a rollout has not reached your region, or when you need a specific version — and only when the publisher has authorized that copy. APKBrowse does not list pirated, cracked, or unauthorized rebuilds of EteSync - Secure Data Sync, and a listing is removed when the evidence for it stops holding up.
Get EteSync - Secure Data Sync
Every source we list for com.etesync.syncadapter is legality-reviewed. Pirated or cracked builds are never offered.
Other sources
F-Droid listing
officialF-Droid builds this app from source and signs it. This is its official listing, with older builds and full release notes.
Source code
verified publisherThe upstream repository this build is compiled from.
We check legality and signature continuity, but device behaviour still varies. Install at your own discretion.
App Information
Security Verification
We record provenance; we do not run malware scans. Verify the hash yourself before installing.
SHA-256 Hash
1ba72af98c30a790a5925f4e59493922efd7109e3b2bffe6510fb6b6671d7be8
Signing certificate
e3a065e54ae1d2002d310b3754d00d4e66cbb71c47528a089c1454e170691780
Permissions Required
Previous Versions
The signing certificate fingerprint for this release is on record, so a build that does not match it did not come from this publisher.
Report a problem with this listing
A listing is only as good as its corrections. If a source is broken, a signature looks wrong, or this app should not be here, tell the moderation team.