Sub application shakes while moving when V-Sync is on (also with a significant frame rate drop). Turn off V-Sync will solve this.
Please check the video:
This issue occurs under both DX9&DX11, a bit better under DX11.
Uncheck display as sprite will stop shaking but there still remains a duplicated edge:
(Besides, if uncheck display as sprite, steam remote play will not be able to catch the content of sub application and remains a black area on phone)
Here follows a simple example that shows the issue: