Fruit: Earns you points when sliced.
Bomb: Does different things in different games, but all bombs (except if you're using the Spirit Bomb Smoothie) have bad consequences.
Frozen banana: Allows you to slow down gameplay for a period of time.
Blue banana: Doubles your score for a period of time.
Red banana: Starts a fruit frenzy.
Smoothies: Unlockables which help you gain a higher score.