Midair is described as 'fast-paced jetpack shooter set in a breathtaking new sci-fi universe. Use movement to your advantage, outwit your enemy from every angle, build defenses, and fully customize the way you play' and is a first-person shooter in the games category. There are four games similar to Midair for Windows, Linux and Mac. The best alternative is Titanfall. It's not free, so if you're looking for a free alternative, you could try Tribes or Legions: Overdrive.
Tribes is a series of five science fiction first-person shooter computer games that marketed between 1998 and 2012. The game plot is set in the far future (2471 - 3940). Represent entire series of Tribes games.
Legions: Overdrive is a first-person shooter originally released by GarageGames for their InstantAction web platform in 2008. Legions features many elements from the Tribes series, including jetpacks and skiing.
Jetball is jetpack soccer. An online multiplayer jetpack sport game. A true FPSZ (Z for Z-Axis) where your movement is aided by a powerful jetpack and impulse weapons. Play online with friends, solo vs bots, cooperative, competitive or casual.