In case you're unfamiliar with this game, please see https://www.howtogeek.com/269207/how-to-enable-android-nougats-cat-collecting-easter-egg/ and skip to the step that says "Give the notification bar a couple more tugs, to expose the Quick Settings menu. Then tap 'Edit.'"
*Keep your cats!*
There is experimental support to "teleport" your cats from the built-in game to this game - even across devices - at the source link below.