Boosters are divided into Bomb, Rainbow, Lightning and Beam Shot.
They can be obtained through daily spins, a chance by reaching many levels, or by purchasing.
These boosters can be found at the bottom of the level.

Here are some brief explanations about the items:
Bomb
: Drop 20+ bubbles to charge the Bomb, Bomb explodes nearby bubbles!
Rainbow
: Rainbow bubbles can be matched with any color!
Lightning
: Can remove a row of bubbles!
Beam Shot
: Pop bubbles 7 times in a row and get the Beam Shot! It blasts everything in its way.