Microsoft updated both Store and Xbox app for Windows 10 mobile devices. However the Xbox app has a number of new features and improvements, but there is not any new change in Store update (v 2015.8.12.1).
The Xbox app has been updated with version 8.8.15003. The latest update brings support for streaming Xbox One games to Windows 10 PCs in 1080p resolution and in 60 FPS along with other new features and improvements.
Thanx keshav for this tip!!!