Yeah so I can link to the tablet holder as this was on thingiverse. It was made to hold the HP Stream 7 tablet as a RC transmitter screen. I modified it in TinkerCAD to suit my needs. If I can work out how I'll link you to the TinkerCAD file, if you want it?
TinkerCAD Link: https://www.thingiverse.com/thing:2939623
I then used these brackets to mount the tablet holder to the frame of the D-Bot