You can configure your ownCloud server to automatically send out e-mail notifications to your users for various events like:
Users can see actions (delete, add, modify) that happen to files they have access to. Sharing actions are only visible to the sharer and sharee.
The Activity App is shipped and enabled by default. If it is not enabled simply go to your ownCloud Apps page to enable it.
To configure your ownCloud to send out e-mail notifications a working Email Configuration is mandatory.
Furthermore it is recommended to configure the background job Webcron or Cron as described in Defining Background Jobs.
There is also a configuration option activity_expire_days available in your config.php (See Config.php Parameters) which allows you to clean-up older activies from the database. .. 2.3 replace:: 2.3