These are the patch notes for everything since launch.

• ufo is now always visible, gets close to your alien car when you are close to the finish. This simplifies finding the exit.
  
• added easier routes to some levels
  
• screenshake when you bump your car into something
  
• added Steam Cloud Saves
  
• smoke exhaust particle effects for driving forward
  
• added bubbles in portrait of Donut Kid while he is underwater
  
• added hotkeys to switch between the cars. On d-pad: ramp, downut, alien, 'this side up' for the box kid.
  
• UI now has rounded bubbles instead of straight
  
• comic book panels has nicer speech bubbles
  
• streamlined some comic book dialogue
  
• added tractor beam when the ufo saves you/you win the race
  
• added fireworks when you beat a level
  
• added massive fireworks when you get a new star for the first time
  
• added bell sound effects when you are too late for the respective speed star
  
• added smoke to the final level. You will find the exit easily
  
• added camera tracking when you switch from one car to the other
  
• turned some town levels into night levels
  
• added particle effects to way signs
  

Thanks for playing so far! And if you are still reading this, consider adding a review, it helps a lot.