I also was hacking a bit PrBoom but don't have time to continue with it. My interest was adding accelerometer support for it. It mapped to forward/backward/strafing and touchscreen to turning. It works fine but need more tuning, also would be nice to map proximity sensor to Fire. BTW, sound works if PrBoom is compiled with SDL mixer disabled.
I could provide my patches to anyone who has time to continue (if they are of any use ):

• accelerometer usage for movement, needs tuning and some configuration support
• fix to enable exit from full screen mode
• disable exit confirmation to be able just close the window from dashboard