Some Windows Phone features take time to reach every part of the world - but Microsoft can also ban OEMs from distributing certain features in some markets, with a $5m penalty for not complying.
A week of Windows 10, holograms and Exploding Kittens on Mars
Office 2016 launching this year, touch apps coming soon
Microsoft reveals the next version of Windows 10
Introducing Windows 10 for phones
Hands on with HoloLens
Download: Windows 10 build 9926