Marvel Avengers Academy was a freemium mobile game for iOS and Android, based on the characters featured in Marvel Comics. It was released on February 4, 2016. The game was shut down on February 4, 2019. Despite the name, the game was not related to the comic series Avengers Academy.
Source: Wikipedia, "Marvel Avengers Academy", available under the CC-BY-SA License.
Experience the Avengers as you’ve never seen them before! Build the ultimate Super Hero academy, and play as your favorite Avengers characters reimagined as students developing their superpowers. Customize your dream campus, unlock your favorite heroes and villains, navigate their social lives, and go on epic missions.
Source: The Marvel Website.