Microsoft has announced that its SmartGlass app for smartphones has been downloaded some 17 million times.
Eurogamer reports that the figure applies to Windows Phone, iOS and Android versions of the app, and Microsoft has stated that 89% of users return to the app within a week, implying it's being used quite regularly.
The app can be used to track your Xbox profile, achievements, messages, friend lists and more, while some games offer extra content and functions via your mobile device. SmartGlass is set to be a regular feature in Xbox One titles, and with an install base like this already in place, it could just take off in next-gen.
What do you think? Are you a SmartGlass user? Let us know what you think of it below.