Ask anything
About patterns in your last few weeks.
Case study · 2026Solo built · iOS first
A journal
that listens
journAI is a private notebook that reads itself back to you. You write a few lines; it answers — quietly, and only when there's something worth saying.
Launching late 2026. No marketing emails — just one note when it opens.
01 · Idea
A notebook that reads back, not a chatbot that talks first.
Most AI products lead with the model. journAI does the opposite — you write first, then the AI sits with what you wrote. It catches the mood. It notices what's recurring. It writes you a short letter every Sunday about the week you just had.
The interface gets out of the way so the writing can do its work. Long-form serif type, almost no chrome, a single accent of pink reserved for the moments where journAI actually has something to say.
It opens on iOS first, with Android to follow. The app works locally first and syncs quietly in the background. The AI never sees your entries on the device — it lives server-side, behind your account, and only ever responds when you ask.
02 · Experience
Three small moments
that make up a week.
Good evening,
Arun.
A
12 days
longest 28 days
journAI
Recent
MON · MAY 25quiet
Project review went better than I'd built it up to be. We caught a real problem early and the room actually relaxed for once.
SUN · MAY 24heavy
Sunday evening fog again. Kept circling the same three things, none of them urgent.
A page you return to.
Greeting, streak, and the last few days at a glance — nothing else.
Today · TuesdayDone
Started the morning with the meeting I was dreading. It went fine — better than fine. The thing I'd been carrying for a week turned out to be twenty minutes of conversation and a clearer way forward.
Funny how the weight always feels heavier the night before. I'm going to try to remember that on Sunday
Funny how the weight always feels heavier the night before. I'm going to try to remember that on Sunday
saving
An empty page that doesn't judge.
Distraction-free serif type, autosave, no word-counter shaming.
Insights
journAI · weekly digest
Your week in words.
MAY 19 — MAY 25The week kept circling the same project review — three days of low-grade dread that mostly dissolved once the conversation began. You're noticing the weight tends to sit in the waiting.
Read the full digest
Mood · last 30 days
A letter, once a week.
A short read-back of your week — themes you returned to, mood you carried.
03 · Features
Six small capabilities,
quietly stitched together.
Distraction-free writing
Serif type, autosave, no word counter. Just a page that lets you finish your thought.
Chat with your journal
Ask "what was on my mind last March?" — journAI answers with the entries it remembers.
Mood & patterns
Every entry gets a quiet read — mood, themes, action items — surfaced over 30 days.
Sunday-night digest
A short letter delivered every Sunday — the week as journAI heard it.
Full-text search
Find the line you half-remember. Fuzzy across years of entries, ranked by relevance.
Private by default
AI runs server-side, behind your account. Keys never touch the device.
04 · How it works
You write. It listens.
It writes back.
Step 01
You write.
Open the app, write a few lines. journAI saves quietly as you go and then takes a moment to read what you wrote.
Step 02
It listens.
A small server-side run picks out mood, themes, and any action items — never on your phone, never on the public model.
Step 03
It reads back.
Ask it anything from the Today screen. On Sunday, it sends a short letter about the week you just had.
05 · Under the hood
A small stack,
chosen with care.
The product reads like a quiet notebook, but most of the interesting work happens out of sight. Every entry triggers a small server-side pass — mood, themes, action items — written into Postgres alongside the entry itself. The same pass keeps an embedding for search and for the conversational "chat with your journal" feature.
The single most important architectural decision was this: the AI never runs on the device. Every prompt is composed in a Supabase Edge Function, signed against the user's session, and only the response comes back. Gemini's API key never sits on a phone. There is no offline LLM path, by design.
The AI runs server-side, behind your session. The keys never touch the device.
The Sunday-night digest is a scheduled Edge Function that walks the week's entries, the mood points and themes attached to them, and asks Gemini to draft a short letter in the second person — the kind of letter a thoughtful friend might write after reading along.
On the client, it's a single Expo / React Native codebase — iOS ships first, Android follows from the same source. Styled with NativeWind, instrumented with PostHog and Sentry. Payments go through RevenueCat so the storefront mess stays at the edges.
Designed, written, and shipped by one person — every screen, every edge case, every line of the digest prompt.
1
Designer & engineer
iOS
At launch · Android to follow
12
Screens · light + dark
0
Keys on the device
06 · WaitlistThe first page
The first page
is the hardest.
journAI opens in late 2026. Leave an email and you'll get a single, quiet note the day it goes live — no other mail, ever.
iOS first. Android to follow. One quiet note when it opens.