Catch the fleeting
Voice, a single line, a fragment — whatever form the thought arrives in, you can set it down immediately. No title, no category, no decisions first.
A private thought journal
Every fleeting thought,
kept.
NianTou (念头) literally means a thought in Chinese. Most of them last only a moment — an insight, a pang, a wish, a half-formed idea — and then they are gone without a trace. NianTou is a strictly private place to set them down: one line or one voice note, time-stamped to the minute, kept for good.
Works in your browser — nothing to install · Android app available
A room with no audience
NianTou assumes, from the ground up, that what you write here is for you alone. So there is no share button, no public feed, no follower count — and no way for another person to stumble across what you wrote.
Entries are encrypted on your device before they are uploaded. The servers hold ciphertext that cannot be turned back into your words. An app lock and PIN code add a further barrier if someone else picks up your phone.
How the encryption works, what the servers can read, and which AI features send text out are set out line by line in encryption and data boundaries; day-to-day questions are answered in the FAQ.
The thoughts you keep to yourself stay yours.
What it does for you
Encrypted on your device
Content is encrypted locally before upload. No feed, no audience, no path by which anyone else could read it.
Timeline and monthly archives
Everything settles onto a single timeline and is bound into monthly volumes, so you can go back to any stretch of your life and find it.
Tags and cross-year comparison
Tag a thought and find it again years later. See what the same theme looked like at different points in your life.
Mood curve and word cloud
Your scattered entries fold into a curve and a word cloud, so you can see how your mood actually moved and what kept recurring.
AI deep insight
Let AI read your entries and surface the threads and loops you had not noticed in your own writing.
Three steps to start
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Write the first one
Open the app and put down whatever you are thinking about right now — a sentence, or a voice note. No title, no category.
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Let it accumulate
Write when something surfaces. One entry a day is plenty. Everything arranges itself along the timeline and into monthly archives.
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Come back and look
Return after a while and meet that stretch of your life again through mood curves, word clouds and AI insight.
Who it is for
Citta assumes nothing about who you are — only that some of your thoughts have nowhere else to go. These are the ways it is used most often.
Catching ideas before they go
Ideas arrive on walks, in transit, just before sleep — and vanish within minutes. Put one into the archive as a single line. You do not need a title, or a folder, or a decision about what it is.
Tracking how you actually feel
Sometimes you cannot explain why the day felt heavy, or why it suddenly felt light. Writing it down is enough. Over time the mood curve surfaces patterns you had not noticed in yourself.
Writing to your future self
Year-over-year comparison puts the same subject side by side across different years, so you can see what you thought then, how it changed, and which worries never really went away.
Saying what cannot be said out loud
Some things you do not want to tell anyone, and would not put anywhere public. There is no share button here and no audience. Writing it down is only about making it a little easier to carry.
What it is not
Being clear about limits is more useful than listing every feature.
Not a medical service
Citta does not provide diagnosis, therapy or crisis intervention. If you are in danger or in ongoing distress, please contact a professional helpline or clinician — we list available services on the support page.
Not a social platform
No follows, no likes, no feed. You will not see anyone else's entries, and they will not see yours.
Not a task manager
There are no to-dos, no reminders and no collaboration. It does not help you get things done; it helps you keep things.
Not a promise of absolute security
Entries are encrypted on your device before upload and the servers hold ciphertext. No software can promise that nothing will ever go wrong, so please protect your device and your account too. When you use the AI features, the relevant text is sent to the model provider in plain text — see the privacy policy.
Frequently asked
What is NianTou?
NianTou (念头) literally means "a thought" in Chinese, and is also known as The Archive of Mind. It is a strictly private journal for the thoughts that arrive and vanish in seconds — an insight, a pang of feeling, a wish, a half-formed idea. You set them down by voice or text the moment they come, each one time-stamped to the minute and kept permanently.
Is what I write actually private?
Yes. Your entries are encrypted on your device before they are uploaded, so the servers store ciphertext that cannot be turned back into your words. The product has no social features, no public feed and no way for another person to discover your entries. An app lock and PIN code add a further barrier if someone picks up your device. One thing worth stating plainly: AI tagging and AI insight need to read your text, so when you use those two features the relevant text is sent to the model provider in plain text. The privacy policy sets this out in full.
Which platforms does it support?
NianTou runs on the web and on Android. The web version works directly in a browser with nothing to install, while the Android app offers a smoother voice-recording experience.
Does it cost anything?
Core journaling and archiving are free. Deeper capabilities — AI deep insight and fuller emotional analysis — unlock through in-app purchase.
How is it different from a regular notes app?
Notes apps are built to organise information: categories, collaboration, fast retrieval — and their contents are implicitly written to be shared or read by others. NianTou is built to set feelings down. It assumes from the ground up that only you will read it: there is no share button, no public feed and no social graph, and entries are stored encrypted. It holds moods and moments rather than tasks and reference material.
How do I start?
Choose "Start writing" above to begin in your browser right away — nothing to install. Android users can download the app for a smoother voice-recording experience. A short three-screen introduction covers capturing, keeping and privacy, and then you can write your first thought.
Some thoughts deserve to be kept
We remember the things we retell often. What slips away are the moments that only flashed once — and those are usually the ones that add up to who a person actually is.