I can put that action into a custom control and it performs in the same way. Though I've only tried this on a web kit browser (Chrome) and not a device. What have you tried?
Here's what I did and using the tutorial from the wiki. I took the new document page and dropped that to a new custom control...
preload="true" resetContent="true">
back="Cancel" moveTo="viewPage">
refreshMode="complete">
targetPage="viewPage" transitionType="slide" direction="Left to Right">
computeWithForm="onsave">
cols="40" rows="10">
And then added back that custom control to the XPages in the same location as the previous was ...
....
And it all worked.
The mobileDemo.xsp from the Demo App does the same thing.