During gameplay, type in these codes (single player
game only): 

jjgod - God mode
jjinv - God mode
jjguns - All weapons
jjammo - All ammo
jjrush - Sugar rush
jjfly - Helicopter ears, type again for hoverboard
jjk - Self destruct
jjshield - Power shield
jjnext - Level skip
jjlight - Fully light level
jjbird - Bird assistance
jjcoins - Get coins
jjgems - Get gems
jjending - Return to main menu
jjq - Quit to desktop
jjmorph - Change into Spaz, type again to become Bird,
type again to become Frog, type a fourth time to 
change back to Jazz.