Hi,
I have developed GCode Simulator & Printer App for Android which allows one to use a tablet/phone with USB-OTG support to control your printer.
Printing from a Galaxy Tab 2 on my Reprap printer with Sprinter/Marlin firmware works great, but I don't know if it works on Ulitmaker printers.
It would be great if Ulitmaker owners could test the GCode Simulator (Free) App and provide feedback.
Find more info on http://www.dietzm.de/gcodesim
Thanks in advance !