Built by Uncle Toe Knee

Where game day
meets craft time.

Sports activity books and apps for tiny fans and the people who love them.

BBaseball
FFootball
BBBasketball
GGolf
SSoccer
The gap we noticed

Most kids' brands skip sports. Most sports brands skip kids.

Walk through the kids' aisle — you'll find unicorns, dinosaurs, and rainbows. Walk through the sports aisle — you'll find adult jerseys and memorabilia. There's almost nothing for the 5-year-old who knows every player on the team.

Heartball is for the kid who wears a jersey to dinner. The kid who wants to draw their favorite player. The kid who's learning their first trivia and won't stop quizzing their parents — or their uncle. Tiny fans deserve their own brand.
What we're making

From paper to pixels.
Fun for every tiny fan.

Coming Q3 2026
📱

The Heartball App

Reusable digital coloring book with three difficulty modes, sports trivia bonuses, and a parent dashboard. No ads. No in-app purchases. Just creativity.

$9.99founder's lifetime pass
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Coming 2027
💧

Magic Water Books

The magic of paint-with-water — but with the players and teams your kid actually loves. Reusable, mess-free, no ink, no crayons.

TBAjoin the waitlist
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Our story

Hi. I'm Uncle Toe Knee.

I'm not a parent. I'm an uncle. And before you wonder if that disqualifies me from building a kids' brand — hear me out.

I grew up memorizing stats off the back of the newspaper sports page. I've played sports my whole life — still do, on a softball league, plus golf and tennis when I can sneak them in. I collect jerseys. I'm a real, lifelong fan.

Then came Niece #1 and Niece #2. Right now they're 2.5 and 1 — too young for half the things I want to share with them. But I already know: I want to be the uncle who passes this on. The jerseys. The stats. The Saturday-morning excitement of game day.

So I went looking for sports stuff at their level. Activity books. Coloring pages. Apps. Something — anything — that took kids' sports fandom seriously.

There was almost nothing. Sports stuff is built for adults. Kids' stuff skips sports entirely.

So I started building what didn't exist.

If my nieces fall in love with sports the way I did — amazing. And if they don't? That's amazing too. Sports teaches good habits and good values no matter where the passion eventually lands. I'll be rooting for them either way.

Someday I hope to be a dad too. Until then, I'm Uncle Toe Knee — and I'm building Heartball for every tiny fan, in every family.

❤️ Uncle Toe Knee

Built for
Tiny fans
Ages 4–8. Three difficulty modes that grow with them.
Inspired by
Nieces #1 & #2
Ages 2.5 and 1. Too young for the products. Future tiny fans in the making.
Built by
One uncle
Lifelong fan. Jersey collector. Softball league regular.
For the grown-ups

Built for kids. Designed for the grown-ups who love them.

🚫

No ads, no tracking

Nothing harvesting your kid's attention or data. Just play.

🎨

Real creativity

Open-ended coloring that builds fine motor skills and focus.

📵

Screen-optional

Start with the printable. Add the app only when ready.

💛

Uncle-built

Every product designed by a real human who loves the tiny fans in his life.

Is this affiliated with the MLB, NFL, NBA, or other leagues?
No. Heartball is independent. We use real team colors — because that's what kids love — paired with fictional player names. No team logos, no real player names. Kid-safe by design.
What ages is this for?
Designed for ages 4–8, with three difficulty modes to grow alongside your child. Younger kids tap to color, older kids stay within the lines.
Are the digital products safe?
Absolutely. No ads, no in-app purchases, no tracking, no chat features. Designed to comply with COPPA from day one.
Can I print the PDF more than once?
Yes — that's the whole point. Reprint as many times as you want. Your kid will color the same player a hundred times and still want one more.
When does the app launch?
Targeting Q3 2026 for iPad. Join the email list for the exact launch date and founder's pricing — that's where launch perks land first.
How can I support Heartball as a bootstrap brand?
Join the email list, share with parent friends, and when products launch, leave a real review. Word-of-mouth is everything for indie brands.
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