During Build, Operating Systems exec Terry Myerson demonstrated how an iOS game could be easily ported to Windows 10.

During the demonstration, Myerson obtained an Xbox Live achievement, "How do you like them Apples?", showing off the integration of Xbox APIs in Windows store apps.

We already have Xbox achievements on some Windows 8 and Windows Phone 8 games which count towards your Xbox gamerscore, a pool of all the points you've accrued playing Xbox branded games. Seeing an achievement pop-up on a very basic math game made some concerned that the Xbox API could become open for any developer to use, regardless of the quality or uniqueness of their game. There's a lot of bad Flappy Bird clones in the store after all.

50 gamerscore for basic arithmetic? Really? Fear not! Microsoft have issued a statement:

...As we announced at GDC, we're delivering an Xbox Live SDK for Windows that enables developers of all sizes to build cross device experiences powered by Xbox Live. The demo showed at //build was for illustrative purposes to show that developers can use code built for Android or iOS apps and easily migrate them to Windows 10. Any use of Xbox Live services, such as awarding Gamerscore, will be in line with current policies, and awarding Gamerscore and earning Achievements requires a certification process for developers...

As expected, it turns out that Terry Myerson's demonstration was just a basic example. For a developer to contribute to the gamerscore pool, they must meet certain standards which will be in-line with what we already have.

...We are committed to bringing the same high quality achievements experience to Windows 10 in a way that does not trivialize or disrupt the gamerscore economy. We'll have more to share on this implementation at a later time...

As an Xbox fan, I've always seen the Xbox APIs as a really strong Windows Phone unique selling point. When I tell Xbox fans that some of their favourite mobile games carry Xbox achievements on Windows Phone, it's always a good hook. Gameloft and other major mobile game developers have reined in their support of the platform for reasons unknown, whilst Game Troopers have risen up to fill some of the Xbox for Windows publishing gap.

As Windows 10 furthers a developer's ability to port their games to and between Windows devices, we can only hope that Xbox for Windows gets the love it deserves (without providing achievements for every single match-three game that floods the store...)