Iron Man 3 by Gameloft is the official tie in game for the movie. In this endless runner game you control Tony Stark aka Iron Man 3. Technically this game is better described as an endless flyer as you go through obstacles and fight enemies, and the action is fast and frenetic and a lot of fun.
In this game the purpose is to collect Stark Credits so you can upgrade your armor and ability while trying to beat numerous enemies. The game is very easy to control as you just need to swipe and tap to attack robots, although the best method is to just keep attacking.
Besides the robots you also have to dodge fighter jets and missiles and in addition there are other objectives that you can play such as collecting an x number of credits of fly this or that length. This feature adds to the variety and prolongs its life.
Iron Man 3 also lets you go against some of the bosses straight from the comics, and what makes it interesting is that Iron Man needs crystals to go on, adding to the challenge. In addition to this, the game allows you to unlock and upgrade your armor. The graphics and sounds are very good and make it worth playing. Watching Iron Man fly through army bases can be quite exhilarating.
Not all games with movie tie-ins are good, but Iron Man 3 is a notable exception. There are IAPs here just like most free games, but that doesn’t take away anything in terms of playability.