Please have a look at some of the frontend related works I have been working on in the previous years.
Here is a very cool mobile racing game I coded with Java for a company called Kuuasema. My work included all the functionality in the game including AI, game mechanics, UI, rendering, physics etc. Please check out a video: https://www.youtube.com/watch?v=3qI4lwUzVJg
And a review: https://www.pocketgamer.com/smash-kart-racing/smash-kart-racing/