We have a new alternative to ownCloud available called “NextCloud”. It is available via https://www.eskimo.com/nextcloud, or by using the Web-Apps drop down menu.
The development of ownCloud seems to have stopped at a point where it is slow and buggy, and limited in features. NextCloud has far more apps and capabilities. Not all apps are configured yet, some require fairly extensive configuration so not all apps are working yet, still the working set is far larger than owncloud.