Client connects to the CMS each collection interval to exchange information (download new content/schedule and update status/stats etc to CMS)
You can see your device's status, current layout in CMS-> displays page.
On that page you can also request a screenshot, which will take a screenshot on your device and send it to the CMS.
On statistics page you can see what was displayed for how long etc.
You can also configure maintenance and email alerts - so it will send you an email when your display goes offline/online.
Other that all that, you can still use remote connection, it's not built-in at the moment and in most cases would require rooted device, but certainly is possible as well.