Thanks notaz, that was exactly what I was looking for.
As for quitting, both q or esc work, but in my experience forcibly quitting leaves the PND mounted. Is gracefully quitting out of Ginge application specific? (My other experience with ginge-wrapped applications is gpFCE-GP2X, and I know that allows you to quit from within the application, and doesn't always preserve your save data via 'q'.)
It's fine if it is, I'm just curious.