Hold the line through a reactor shaft. The tunnel comes at you, the ship is yours to fly, and the score only stops when you do.
A new pilot starts in Shaft 7. Fly through a world and the next one opens: Kessa Basin, Stonefall Canyon, Frostline Pass, Ember Rift, Hollowdeep, Neon Sprawl, Stormwall, and the Kármán Line. Every world you have reached stays available.
Fly a stock ship, or build one. A build has a frame, paint, trim, and engine glow, plus speed, handling, and boost. The ship that set a score can be opened from the scores list.
The game runs on the phone. Best scores, ships, and unlocks are saved on that device. There is no account. The score table in this version is the one on your phone.
Worlds also open by flying. If you would rather open all nine at once, or upgrade a ship, that purchase is made with your Apple ID on iPhone or your Google account on Android. Special paints, trims, and engine glows are kept by the store for your account. Speed, handling, and boost upgrades belong to the ship on that phone.
Reactor Run is built for iPhone and Android. On iPhone it needs iOS 15 or later. iPad runs the iPhone version.