DAVx⁵ is an open-source app for Android that lets you sync your calendar, contacts, and tasks with your own server—completely without Google services. It's a central tool if you value data privacy and want to manage your data yourself.

What is DAVx⁵?

DAVx⁵ (pronounced "DAV-ex-five") is an Android app that acts as a synchronization adapter. It connects your smartphone to CalDAV and CardDAV servers, allowing you to synchronize your calendars, contacts, and tasks with your own server or a privacy-friendly provider (e.g., Nextcloud, mailbox.org, Posteo, Fastmail).

Unlike Google accounts, this gives you full control over your data.

DAVx⁵ Features

• CalDAV Synchronization: Synchronize calendars (personal & business) between server and phone
• CardDAV Synchronization: Securely store contacts on your server
• Task Synchronization: Can be used with the OpenTasks app, for example
• Manage multiple accounts: Ideal for personal and professional calendars
• Offline Support: Data remains available locally
• Open Source & GDPR-compliant

Typical Use Cases

• Self-Hosting: Synchronization with Nextcloud or your own CalDAV/CardDAV servers
• Google-free Android: Calendar & Contacts without a Google account
• Privacy-friendly email providers: mailbox.org, Posteo, Fastmail, etc.
• Corporate solutions: Integration of groupware servers (e.g., SOGo, Radicale, Baïkal)

Disadvantages

• Setup requires basic technical knowledge (server URLs, passwords, etc.)
• Android only: For iOS, you need other solutions (e.g., native CalDAV/CardDAV integration)
• Paid app in the Play Store (but open source – APKs are available for free on F-Droid, for example)

Conclusion

DAVx⁵ is the Swiss Army knife for synchronization on Android. Anyone who values ​​privacy or wants to avoid Google services will find this app indispensable. Together with Nextcloud or a privacy-friendly email provider, you can operate a completely Google-free smartphone – with full control over your calendars, contacts, and tasks.