Celestrike vs Kerbal Space Program
Published 19 October 2026 · All guides
In short: Kerbal Space Program is a sandbox about building rockets and getting them somewhere. Celestrike is a strategy game about what satellites do once they are in orbit: watch, listen and fight. Both treat orbital mechanics as real. KSP is on PC and consoles and is no longer being developed; Celestrike is free on iPhone and Android. Written by Celestrike's developer.
What you actually do
Kerbal Space Program: design a rocket from parts, launch it, fly it by hand into orbit and on to other planets and moons, and bring the crew home. Most of the challenge is engineering and piloting.
Celestrike: satellites arrive in orbit by buying them; there is no launch to fly. You decide which ground sites each satellite targets, whether to spend propellant changing its orbit, what to upgrade, and when to take on other satellites. Most of the challenge is planning and choosing.
The physics
Kerbal Space Program simulates flight in detail around a fictional, scaled-down solar system: thrust, drag, staging, and orbits that follow Newton's laws, with each body's pull handled one at a time.
Celestrike uses the real Earth at full size and models orbits the way mission planners do, as elements that change over time, including the slow turn the Earth's bulge gives every orbit. You never steer a burn by hand; you choose a manoeuvre and the game shows what it costs in propellant and time before you commit.
Time
Kerbal Space Program runs while you play, and you speed time up to skip long coasts.
Celestrike follows the real clock, accelerated, and keeps running with the app closed, so a satellite's next pass over a site happens whether or not you are watching. Sessions are a few minutes long.
Setting and tone
Kerbal Space Program is cheerful, with the little green Kerbals as the crew and space exploration as the goal.
Celestrike is a cold-war-style espionage game: secret sites, stolen technology, satellites fighting satellites, and a thread of things in orbit that answer to no registry.
Platforms, price and status
- Kerbal Space Program: PC (2015), then PlayStation and Xbox. A one-off purchase. Its last major update was 1.12 in 2021. The sequel, KSP 2, is on Windows in early access and has had no updates since its studio closed in 2024.
- Celestrike: iPhone and Android, released in 2026 and actively updated. Free, no ads, no accounts; the only purchase is optional packs of fast-forward hours.
Which is for you?
If you want to build things and fly them, Kerbal Space Program is still the game to play, on a computer or console. If you want orbits in your pocket and enjoy strategy more than construction, try Celestrike. If you have played KSP, Celestrike's orbits will feel familiar: the same rules, used for a different job.
Where Celestrike comes in
Celestrike is a free download, so the easiest way to compare is to try it. Celestrike is a free spy-satellite strategy game for iPhone and Android, played on real orbits — on the App Store and Google Play.
More guides
- Games like Kerbal Space Program on iPhone and Android
- Orbital mechanics without the maths
- Celestrike vs XCOM 2