The large hotel chain is in the late testing stages of their Windows Phone app, and it should be in the Store by May 11.

Despite some apps disappearing from the Windows Phone, in recent weeks we have seen more official ones arriving. We can now add Marriott International to that list.

According to our tipster, the app experience is so far superb:

"Seems full featured and on par with our other OS apps. It has maps, hotel photo galleries, booking, check-in, Marriott Rewards integration, local restaurants, etc."

Besides Marriott, Windows Phone and Windows 8.1 users also have the excellent Hotel Tonight and Hilton HHonors for booking rooms for their vacations.

We will keep an eye out for the Marriott Hotel app to go live, but it should not be much longer.

Thanks, Derrick H., for the info!