https://www.nhtsa.gov/recalls - can check without app too. Also you can click on "vehicles" and get free access to technical service bulletins (TSB). And complaints about the car :)
I randomly caught a serious fire-risk recall on a relative's car a while ago, and afterwards thought... there should be a .gov app for that. Well, there is!
Anton Yelchin was killed by the laxness of a major recall on his Jeep. This is a real issue which can largely be solved by an app like this.
