Love this kind of game and you executed it nicely!
- Start very simple with just one piece of fruit that you have
to push to the mouth. Maybe even with an arrow in the background
so as to know where the fruit has to go. Just for the starting level(s)
- Undo button (Important one, maybe penalty point for using it?)
- Hi-score list with number of steps taken to complete level
- The text between the levels doesn't change except for the last.
You almost have a story going on, maybe you should vary a little?
- I see potential of growing this into a larger game and maybe even
ask a little money for it! This could be the free-version
Mickelukas had a good suggestion for extra elements. You can
even introduce a female which you have to feed. Or even harder
an animal that eats certain fruit if it can get to it ... etc..
Good job so far!
Best regards from