Here is the full list of all 22 Ever Seen A Cat? achievements. It takes around 1-2 hours to unlock all of the achievements on Windows.
Find 1000 cats from any place.
Got all the achievements!
Find all the individual cats in the abstract place.
Cleared all places one time.
Find all the individual cats in candyland.
Cleared candyland for the first time.
Find all the individual cats in the park.
Cleared the park for the first time.
Find 500 cats from any place.
Find all the individual cats in the field.
Cleared the field for the first time.
Find all the individual cats in the home.
Cleared the home for the first time.
Find all the individual cats in the galaxy.
Cleared the galaxy for the first time.
Find all the individual cats in the town.
Find all the individual cats in the forest.
Find all the individual cats in the garden.
Cleared the town for the first time.
Find 100 cats from any place.
Cleared the forest for the first time.
Cleared the garden for the first time.