Planetia — Solar System for Kids
An interactive 3D solar system built for curious kids (and the parents who can't answer all their space questions).
Planetia is an iPad app for children ages 5–9. Six modes to explore, compare, quiz, customize, and build their own solar systems. 3D planets rendered with RealityKit. No ads. No in-app purchases. No data collection. Just space.
What kids can do
Explore — Fly through an interactive 3D solar system. Tap any planet to see facts, stats, and details written for kids who ask "but why?" a lot.
Compare — See all the planets lined up by size, or spread out by distance from the Sun. The kind of visual that makes Jupiter's scale actually click.
Quiz — True or false, multiple choice, find-the-planet, and put-them-in-order challenges. Kids earn badges and climb ranks from Space Cadet to Admiral. A daily question builds a streak.
Customize — Pick colors and paint any planet. Add stripes, polka dots, hearts, stars. Make Mars purple. Creative play meets space science.
What If? — What happens if Jupiter disappears? What if Earth had two suns? Kids change the rules and watch what happens to the orbits. Real gravitational physics, made playful. They can also build custom experiments from scratch.
Build Your Own — Place stars, planets, and moons wherever you want. Set colors, sizes, orbit speeds. Then switch to gravity mode and see if your creation survives real physics.
Why I built this
My kids are obsessed with space. One of them asks questions I have to Google ("Dad, what happens if two planets crash?"). The other wants to paint Jupiter purple and give it three rings.
I couldn't find an app that did both — teach real science and let kids mess around creatively. So I built one. I had zero Swift experience when I started. The entire app was built using Claude Code as my primary development tool, with me writing specs and prompts and Claude writing the code. It took months of evenings and weekends. My kids were the test team. They're the harshest testers you'll find — if something's boring, they just walk away from the iPad.
I wrote up the full story — from the browser prototype to the App Store submission, including the parts that were actually hard. Read it here →
Details
- Platform
- iPad only
- Ages
- 5–9
- Price
- Free. Everything included, nothing locked.
- Size
- 15.5 MB
- Built with
- SwiftUI, RealityKit
- Data collection
- None. No analytics, no tracking, no accounts. COPPA compliant.