Apps on the App Store, and the notes from building them.
A second brain where what you save comes back. Share posts, articles, and YouTube talks in; AI turns them into cards.
Vocabulary learning on the home screen widget — no app to open, you learn at every unlock.
A clean Pomodoro focus timer you can use instantly, even if you have never heard of Pomodoro.
Log your baby's day in 3 seconds. Quick entry, voice input, family sync, gentle on night eyes.
The "chart" you see in the App Store is your country's chart. The United States, Japan, and Taiwan each have their own — not translations of one ranking, but three independent lists. Apple has never offered a global chart at all.
A solo product has no PM to set priorities, but the product-management work does not disappear. Who needs a feature, why it matters now, and when to stop all return to the same person.
When AI returns an empty response, times out, or breaks the expected format, a product knows to stop. The harder case is a fluent, valid response that drops a constraint or makes the wrong judgment.
When an article looks important but there is no time to read it, saving it for later feels reasonable. Nothing is discarded, and we do not have to admit that we may never return.
KofAI Note 1.0.0 is now on the App Store. Its current promise can be compressed into one line: “Capture in one tap, and let AI read it for you.” That explains what the product does without defining what the user ultimately gains.
I have a row of "watch later" YouTube talks, each one easily half an hour, each one still unopened. Saving is quick; turning it into something in my head is the cost I keep deferring.
BabyDay did not begin with a product plan. Our second child was on the way, and the records from our first were scattered across LINE, phone notes, and paper. When we tried to look back, none of it lined up.
I honestly never planned to build a Pomodoro timer.
Starting on Medium felt unfamiliar. I was used to expressing ideas through code, and an empty writing editor was harder than I expected.