Video Based Screen Sharing (VbSS) comes to iOS and Android Mobile SfB Clients
Traditionally Skype for Business (and Lync) uses Remote Desktop Protocol (RDP) to screen share, this gives easy remote control but can be more bandwidth intensive than using a video codec.
Jeff has a great write up on it here: http://blog.schertz.name/2015/10/video-based-screen-sharing-in-skype-for-business/
It’s in Skype for Business Online now, and came to server in CU3, and now the mobile client support it too:
Android (thanks Shoulun Wang on twitter)