A lot or a little?
Parents need to know that Pokemon Rumble Rush is a free-to-play action game for iOS and Android devices. The game has optional in-app purchases, containing a loading screen banner ad. Its collection-oriented gameplay encourages the purchase of in-app currency (which speeds up progress) and hours of repetitious time with the game as kids try to "catch" all the Pokemon monsters. Combat between monsters happens, but there's no blood or gore shown, and defeated monsters fade from view. Otherwise, there's no inappropriate content in the game. Read the developer's privacy policy for details on how your (or your kids') information is collected, used, and shared and any choices you may have in the matter, and note that privacy policies and terms of service frequently change.