Terry Myerson, Microsoft's executive VP of operating systems, announced in March that "a select group of Xiaomi Mi 4 power users will be invited to help test Windows 10 and contribute to its future release later this year. These power users will have the opportunity to download the Windows 10 Technical Preview - installing it and providing their feedback to Microsoft."
Like most of the world, Microsoft needs all the help it can get to put Windows into Chinese smartphones. According to Kantar Worldpanel ComTech, Windows Phone has only 0.8 percent share of the Chinese smartphone market.
This new offer isn't likely to immediately help Microsoft's Chinese mobile marketshare, but it does show Microsoft reaching out to the country's power users. In addition, it makes it clear that Microsoft still wants a slice of the Android marketshare pie for Windows.