Yes one can roll back but it may depend on your version. Most if not all roll back methods are for the older first gen v4.x My Clouds. Unknown if those methods will work on the newer second gen v2.x My Cloud. See the following link:
http://community.wd.com/t/wd-my-cloud-v4-x-and-v2-x-firmware-versions-download-links/148533
On the iOS app problem. As indicated at the WD status link lluna posted earlier there were some problems with MyCloud Account Logins. While that status update claimed remote apps were not affected its possible they might have been.
If the iOS WD App worked in the past but doesn’t today did the iOS device get updated recently? Sometimes removing the app and reinstalling it may fix some issues.
