Earl's comments on PIPO S2 for firmware upgrade_19th Feb 2013;
Tried successful upgrade the following firmwares for the PIPO S2 but still 3DR radio not working and hence Andropilot and DroidPlanner also not working. However same 3DR radio is working on Andropilot and Droidplanner on my other two tabs IS701C and IS709C.
I just got my Pipo S2 to connect directly to my 3DR radio by flashing this rom:
and then downloading an app called 'usb host check', and then running the fix inside there which restores the missing files it needs for the USB host to work.
Will give it some proper testing tomorrow, but it's looking good so far.