It isn't. The controls and physics engine are the best I can think of for such an small and simple game. The triangle pointing up is your forward thruster, the left-right triangles are your rotation thrusters and the big square is an stop rotation switch. The difficulty? You have to dock exactly in the docking connector, and the fuel is quite tightly packed. Start thrusting randomly and you'll be lost in space.
Non-affiliate iTunes link: Lunarcy (0.79€, 0.99$)
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