Focus & Flow: practicing alone, and knowing you're doing it right

The problem

Many people who stutter learn a few techniques from a speech therapist: slow down, start each phrase gently, and let the voice run from one word into the next. Then the sessions end, and they practice alone for months without knowing whether they are doing it well.

The plan I wrote

The app measures the techniques themselves, not "stutters": pace against the band the person chooses, whether each phrase starts gently or hard, and where the voice breaks off inside a phrase. In a noisy place it says "Too noisy to measure right now" instead of guessing.

In earphones it can play the voice back a moment late, which helps many people speak more smoothly. Earbuds add their own delay, so the app measures it and tells the real delay. Nothing is recorded: the voice lives in memory for one practice, and only the numbers stay. It is a practice companion, not a treatment.

The build

AI coding agents built it from my written specification. My work was the specification, the tests it had to pass, and the review. The tests came first: 434 test recordings were fixed before any measuring code existed, and no test is ever edited to make the code pass.

The proof

One review caught the failure this app must never have. An agent delivered the practice screens in minutes, but the results on them were numbers copied from my own example story, not measured. It went back. Now every number on screen comes from the engine or the saved practice.

20 of 22 engine checks pass. The two that fail stay marked as failed; a bar is never lowered to make a test pass. On a real phone, the first-use microphone flow worked, and a recording too noisy to measure was refused, as it should be. Pace through a room reads low, so that is the next update's task.

The launch

Live on Google Play since September 24, 2026, with its privacy page and screenshots for phones and tablets.