Hi,

There are few different ways to earn free boosters.

Once your Team IQ score (your and your friends scores combined) reaches the different Team IQ reward levels (2K, 6K, 10K, 20K, 30K), you'll receive certain free boosters in the game.

You can see the different Team IQ reward levels on the top left corner of Bubbles IQ, marked with light bubbles. If you want, you can also view the different booster prizes of each level by moving the cursor (which usually can be seen as an arrow) over the light bubbles.

Also, at the end of every weekly challenge the best male and female of city, country and global lists will be rewarded with King and Queen rewards!

Best regards,
Bubbles IQ Support Team