Rondo – Prime Factorization
Watch numbers dance & sing
About
Explore the mathematical beauty of numbers through interactive, animated factorization diagrams. Watch numbers dance, hear their unique songs, and even visualize them in augmented reality. Discover the stories behind special numbers and personalize your experience with customizable palettes and sounds.
What's New in Rondo
1.2.0
July 20, 2026
The numbers now take you places. • Collatz Orbit: pick a number and ride its journey all the way down to 1, with a supernova when it soars past what dots can draw. Start it from Settings. • Fluid scrub: flick the dance and it coasts with real momentum, buzzing through the primes as it slows. • Special-number days: opt in to a gentle heads-up when the day of the year is itself a special number, like day 233. • Plus a small maker's mark on shared cards and quiet improvements under the hood. No ads, no tracking, no account, ever. Thanks for dancing with us.
MoreIn-App Purchases
$1.99
Tip a prime · 199
An indivisible prime tip of 199. Pure thanks.
Developer apps
FAQ
What is Rondo?
Rondo is an educational app that visualizes numbers as prime factorization diagrams, allowing users to watch, hear, and explore their mathematical structure. It functions as a math toy, teaching tool, and ambient art experience.
How does Rondo teach prime factorization?
Rondo displays each number as nested rings of colored dots representing its prime factors. Users can interact with these diagrams, pause the animation, scrub through numbers, and even see the factorization in augmented reality.
Can I use Rondo without an internet connection?
The core functionality of Rondo, including watching and exploring factorization diagrams, is available offline. Augmented reality features may require an internet connection for initial processing or specific AR capabilities.
What devices does Rondo support?
Rondo is designed for iPhone, iPad, and Apple Watch, offering a consistent experience across Apple devices. Widgets are also available for Home Screen, Lock Screen, and StandBy.
Does Rondo have ads?
No, Rondo is designed to be calm and free from distractions. It does not contain advertisements, tracking, or require an account.
What features are included in Rondo Pro?
Rondo Pro is a one-time unlock that offers new color palettes, backgrounds, a living clock face, number sequences (multiples, primes, Fibonacci), advanced sound customization, and narrated number stories.
How often is Rondo updated?
Rondo was last updated on July 2, 2026, to version 1.1.0. Updates typically include new features, performance improvements, and bug fixes to enhance the user experience.
What is the age rating for Rondo?
Rondo has an age rating of 4+, making it suitable for young learners and individuals of all ages interested in mathematics. It features full VoiceOver support for accessibility.