Just bought my GS-911 WiFi a month ago and have only just started to use it. Did a tune-up using it this weekend.
I loaded the GS-911 application onto an Asus VivoTab 8 tablet (quad-core, 2GB of memory and 32GB storage), running Windows 8.1, and all works well and is quite portable. Also running the BMW RepRom and a whole lot of other applications on it.
I've also loaded the application onto a Windows 10 (beta) laptop and so for it seems to be working fine. Windows 10 is also lots better than Windows 8.x. I'll keep you posted as I get more info.