Display
Apps render to a virtual 8×8 buffer; larger displays show that source scaled up and centred. Per-app responsive scaling is a follow-up; see each app's doc.
Input
Navigate the on-display launcher with the D-pad. Tap center to select. Or use the quick-launch panel on the left to jump straight to an app.
Tab to the joystick widget; arrow keys + space drive it. Tab to the slide widget for space-to-toggle.
Hold center for 1.5 s during play to return to the launcher.