A kids' math app without dark patterns
I wanted to find an iPad game where my 5yo could learn math, which sounded simple. Turns out most kids' educational apps are... shady. Notifications, streak mechanics, ads for games definitely not meant for children, coin systems and flashy rewards designed to maximize engagement rather than learning. So I decided to vibe code something for her. The result is Lumi. It's a simple math app with: - No ads, no accounts, no tracking - No notifications - No coins, streaks, or variable reward nonsense - Daily limits (because kids should go play outside) - Works offline, stores everything locally -…
In plain words
Lumi is a math learning app for young children that removes manipulative design practices found in most educational apps. It features no ads, accounts, tracking, notifications, coins, streaks, or variable rewards—instead using simple daily limits to encourage balanced screen time. The app works offline, stores data locally, and adapts problems to each child's level. Available in multiple languages, it is free and open source.
written from the facts on this page · September 2026
From the sources
In the maker’s words, at launch
I wanted to find an iPad game where my 5yo could learn math, which sounded simple. Turns out most kids' educational apps are... shady. Notifications, streak mechanics, ads for games definitely not meant for children, coin systems and flashy rewards designed to maximize engagement rather than learning. So I decided to vibe code something for her. The result is Lumi. It's a simple math app with: - No ads, no accounts, no tracking - No notifications - No coins, streaks, or variable reward nonsense - Daily limits (because kids should go play outside) - Works offline, stores everything locally - Supports English, Portuguese, German, French (more to come) My daughter has been using it for a while now and actually enjoys it. The problems adapt to her level, and when she hits the daily limit, it just tells her to go do something else. It's completely free and open source. I built it for her, but figured other parents might find it useful too. https://playlumi.app/ https://github.com/matheusml/lumi Happy to answer questions about the tech stack (SvelteKit, TypeScript), decisions, or anything else
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