Me too.
I have a Lenovo S930 running Android 4.4.2.
Upon attempting to start WD My Cloud app, the screen goes black (except for the Notification Area - the top bar with the notification, network, wifi and battery icons). Then the notification area alternates between landscape and potrait modes a few times despite the phone staying completely still. It does this until the screen times out.
I hope WD can come up with a solution. Really looking forward to access my NAS from my mobile.
Thank you.