NextCloud is a fork of OwnCloud and as the name suggests it is a solution similar to content sharing services iCloud, DropBox, OneDrive, etc. However, the difference is that the user can run it himself and is not so dependent on a third party and often higher speed and availability thanks to the local location of the server.
NextCloud pays € 5,000 for finding a bug – motivating the community to investigate and look for security vulnerabilities. The documentation contains a number of types to increase security and draws attention to some problems in the settings itself in the administration interface.
Nextcloud offers a lot of great free extensions to install in its appstore. For example, calendar, RSS reader, e-mail, tasks, office applications, notes, diagrams, drawings, multimedia, GPS tracker, games and much more.