What If You Could Build for Everyone?

Since the beginning of the internet, building for everyone was a privilege for those who could afford it. Today it belongs to anyone with an idea.

If Kai had existed ten years ago, I wouldn't have had anything close to the legal career I had.

I spent those years helping companies answer the same question again and again. What should this person, at this age, in this country, get to do? The answer was different everywhere, and it never sat still.

It still doesn't. In September and October alone, nine countries and the EU moved on how old you have to be to use social media. Thirteen in Germany. Fifteen in France, Denmark, Greece and Türkiye. Sixteen in the UK. PEGI started moving games with paid loot boxes up to a 16 rating. Mexico told platforms, games and app stores included, that a self-declared age is no longer enough.

Last quarter, more than 3,500 updates changed what a user is allowed to do somewhere in the world.

That's nearly 40 each day.

Now picture you're a two-person team that shipped a game with chat and loot boxes in August.

Your age rating in Europe may have just jumped to 16. Mexico wants more than a birthday field. And if the Philippines' new bill becomes law, your chat is off limits there to anyone under 13.

Each of those means a lawyer and a sprint you didn't plan for, and next month brings more.

Keeping up took enough money, enough lawyers, enough engineers and enough time. Most builders never had enough. So they built for fewer people. Thirteen and up. One country at a time. Or every user treated as an adult, and fingers crossed.

For the last two years we've chased one idea. What if all of it could be distilled into a single button? We dreamed of it as the "solve it" button.

Today it's live, and it's called Kai.

We believe the impact it will have on how everything is built cannot be overstated.

Every app already ships with cloud storage, a database, login and payments. From today, if you're launching anything online, Kai belongs on that list.

Once You See It, You Can't Unsee It

Kai is one SDK. You tell it what you're building and who it's for, add it to your app, and it does the rest. It audits, it configures, it integrates, it stays current. Think of it as self-driving k-ID. In the time it takes to read this post, it can be done.

Who can chat. Who can buy. When a parent should get a say. What a nine-year-old sees, and what a sixteen-year-old gets instead. Kai works it out for every person, in every country, live. When the next country moves, your app moves with it, with no new code.

Every product we've built over the past two and a half years, every feature we've shipped, every lesson we've learned, is inside it.

Now it's available to everyone.

Every App, Every Builder

Every app, game, marketplace, payment network, connected device, AI companion and vibe-coded weekend project has people of every age using it. Kai works for all of them.

And for anyone building them. A solo developer. A two-person AI startup. An indie studio. The largest platforms in the world. A single age check on one feature or a twenty-feature global launch takes Kai exactly the same time.

Built in a Day

Last week, at Google in San Francisco, we handed Kai to 38 builders at the first Build for Everyone hackathon. The brief was one line. Build something that works for every age.

Nobody spent the day reading regulations.

They spent it asking what would delight a nine-year-old, and what a sixteen-year-old would want instead. The gaming winner, Ollie Ollie Out!, is a scavenger hunt for a kid, a real-world exploration game for a teen and a way to meet people nearby for an adult. One app, three experiences, built in a day. Freetime, Curio and Growfolio won consumer AI, education and commerce.

Take the compliance question away and what's left are product questions.

Great teams want to get what they build into the hands of everyone.

What Does It Cost?

Kai is free for your first 10,000 users a month, on every app you build.

We did that on purpose. For as long as I've worked in this space, whether kids and teens got an experience built for them came down to whether the company behind the app could afford it. That ends today. It no longer takes enough money, enough lawyers, enough engineers and enough time.

It takes minutes.

Kai is live today at k-id.com/kai.

What will you build for everyone?