Today we’re opening Antheo to its first beta testers, on iPhone.

It started as a summer project: a dad and his 9-year-old in Barcelona, both learning Spanish, both wanting an app that taught the things we actually say instead of “the lion eats bread.” A few weeks of building later, the whole loop works end to end, and it’s good enough that we want other people in it.

The core loop

Everything in Antheo is built around one small habit: capture a real sentence, then drill it until it’s second nature. Three moves.

Record it. Say the sentence you actually need out loud, or type it. Not a textbook line. The thing you wanted to say at the dog park this morning and couldn’t. “Can you hold the gate for me?” “What’s your dog’s name?”

Translate it. Antheo turns your sentence into the way people really talk, not the stiff textbook version, and shows it to you first so you can tweak it before it’s locked in. A natural voice speaks it aloud, generated once, up front, so it plays back instantly forever, even with no signal.

Drill it until it sticks. This is the part most apps skip. Your sentence goes into a library that’s yours, and then you practice it, hands-free, on a walk or in the car, until you don’t have to think about it anymore. That’s the whole point. Not a streak. Not a badge. The moment the words come out without translating in your head first.

What’s actually in the beta

The practice side turned out to be where the app came alive, so there’s more there than we first planned:

The Train hub. Four ways to drill the same cards. Audio Loop plays your line, a pause, then the answer, hands-free and looping. Voice Lab is record-and-compare: hear it, say it yourself, play yourself back against the model. Flashcards with a quick self-rating. And Fill-in-the-blank, which builds a quiz from your own sentences, with the wrong answers pulled from words you’ve actually used.
Tap any word to understand it. Tap a Spanish word anywhere and Antheo tells you what it means right there, in the context of that sentence, not a bare dictionary entry.
It organizes itself. Every sentence gets tagged by topic as you create it, so a growing library stays easy to search. Group them into decks when you want to, or don’t.
Earn “mastered,” don’t just tick a box. A card only counts as mastered after you pass a quick check on it across several different days. If it starts slipping, it comes back.
Works offline. Download a deck and it plays with no signal, on the plane or the metro.
Spanish, two ways. Castilian to start, with Latin American Spanish selectable too.

And the things we deliberately left out: no streaks, no points, no leagues, no owl guilt-tripping you at 9pm. The reward is understanding the people in your actual life. We wrote about why if you want the longer version.

How to get in

The beta is invite-based to start, so we can keep it small and actually respond to what testers tell us. It runs on iPhone (and on iPad in compatibility mode) through TestFlight.

If you want in, leave your email and we’ll send you an invite. If you’re already on the list, yours is coming.

We’ll keep building in the open. Tell us what breaks.

Barcelona, summer 2026.