Air Bubble

Air Bubbles are big bubbles that helps Sonic breath.

Sonic the Hedgehog (16-bit)
The Air Bubbles appeared in Labyrinth Zone and Scrap Brain Zone Act 3.

Sonic the Hedgehog (8-bit)
Air Bubbles only appeared in Labyrinth Zone.

Sonic the Hedgehog 2 (16-bit)
Air Bubbles appeared in Aquatic Ruin Zone.

Sonic the Hedgehog2 (8-bit)
They also appeared in Aqua Lake Zone.

Sonic Chaos
The bubbles appeared in Aqua Planet Zone.

Sonic the Hedgehog 3
They appear in Hydrocity Zone and Launch Base Zone Act 2.

Sonic Triple Trouble
Air Bubbles appear in Tidal Plant Zone, although not only they help you breath they can also lift Sonic upward.

Sonic CD
The bubble appeared in a level called Tidal Tempest.

Sonic Blast
Air Bubbles appears in Blue Marine Zone.

Sonic Pocket Adventure
Air Bubbles appear in Aquatic Relix Zone.

Adventures of Sonic the Hedgehog
In the episode "Robotnik Jr." when Robotnik and his son drop him in the sewer Sonic inhale Air Bubbles so he can breath.

Sonic X
A Air Bubble appear in the episode "The Light in the Darkness" which help Sonic and Amy out of Final Nova.