EteSync appEteSync is Security tool that is open source under the GPL-3.0-only license. 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.
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.