I ordered 2, 1 for each ShapeOko 2 CNCs. $190.-
http://www.directron.com/ntl31aa008.html
Full fledged tablet PC, I'm planning on connecting keyboard & mouse via Bluetooh. It also has WiFi, USB, and MicroSD card slot.
The Easel web app can run offline once started.
I think I'm all set !

