- [SabreDAV](http://sabre.io/) - Open source CardDAV, CalDAV, and WebDAV framework and server. ([Source Code](https://github.com/sabre-io/dav)) `MIT``PHP`
- [Xandikos](https://www.xandikos.org/) - Open source CardDAV, CalDAV and WebDAV server with minimal administrative overhead, backed by a Git repository. ([Source Code](https://github.com/jelmer/xandikos)) `GPL-3.0``Python`
_CalDAV or CardDAV clients._
_CalDAV or CardDAV web-based clients._
- [AgenDAV](http://agendav.org/) - Multilanguage CalDAV web client with a rich AJAX interface and shared calendars support. ([Source Code](https://github.com/agendav/agendav)) `GPL-3.0``PHP`
- [DAVDroid](https://www.davdroid.com/) - Open-source CalDAV/CardDAV suite and sync app for Android. ([Source Code](https://gitlab.com/bitfireAT/davdroid)) `GPL-3.0``Java`
- [InfCloud](https://www.inf-it.com/open-source/clients/infcloud/) - Open source CalDAV/CardDAV web client implementation. ([Demo](https://www.inf-it.com/infcloud/), [Source Code](https://www.inf-it.com/InfCloud_0.13.1.zip)) `AGPL-3.0``Javascript`
- [EteSync Web](https://www.etesync.com/faq/#web-client) - EteSync's official Web-based client (i.e., their Web app). ([Demo](https://client.etesync.com/), [Source Code](https://github.com/etesync/etesync-web)) `AGPL-3.0``TypeScript`