Any idea how to toggle flight assist when there is no hardware menu button? I'm on the Asus Padfone in tablet mode. I guess I could attach the keyboard and define a key for it but I'd rather play with just he tablet.

The menu button isn't always labeled "Menu," nor it necessarily always hardware. Try pressing all of the system buttons on screen and off. Though, looking at pictures of the Asus PadFone, i think it's the one that looks like two stacked windows.

On Android 4.0 with devices that have 'virtual' buttons for home/back/menu it's the one that looks like 3 dots.