There is no account to create
Kokoro Nikki lives on your phone. Get it, open it, write three sentences.
If you came looking for a sign-up page, there is not one, and that is the point. Kokoro Nikki has no login, no password, no email address and no web version: your journal is stored on your phone, so there is nothing to register for and nobody to register with. Everything worth knowing before the first entry fits on this page.
1. Get the app
Kokoro Nikki (心の日記) is published on the App Store and on Google Play, and downloading it is free. Those two listings are the app: https://apps.apple.com/us/app/kokoro-nikki-ai-diary/id6759742651 and https://play.google.com/store/apps/details?id=com.cre8labs.kokorononikki. There is no web app and no desktop version. The site you are reading now describes the app; you cannot write an entry here.
2. Open it and write three sentences
There is no setup wizard, no onboarding questionnaire and no permission to grant before you can write. The app opens on a blank page dated today. The only thing it ever asks for is a name to greet you by — optional, and you can change or clear it whenever you want. Three sentences is enough for a first entry; the app is built around that, not around long-form writing.
3. The free trial, exactly as it works
Downloading costs nothing. The annual plan comes with a 7-day free trial that you start through the App Store or Google Play, so a payment method is required. On day 7 it converts automatically into the paid annual subscription unless you cancel before then, and you can cancel at any time from your store subscription settings. The monthly plan is a direct purchase with no trial. There are no ads.
4. Writing with your voice
You can press the microphone and talk instead of typing. Your phone's own speech recognition turns the speech into text, which means Apple or Google may process the audio in order to do it. The recording itself is never uploaded to us, and the audio file stays on the device. You never have to use it: typing is the default.
5. Your journal lives on the phone — and what that costs you
Entries are stored in the app's private database on your device, behind your phone's own encryption. There is no cloud sync and no copy of your journal on any server of ours. That is the privacy promise, and it is also the practical catch: a new phone starts with an empty journal, and deleting the app takes the entries with it. Before either happens, use the export in Settings — it writes your whole journal to a single Markdown file with a complete JSON block inside, with or without a subscription. Be clear about what that file is: the app has no import, so it is a readable archive you keep, not a backup that restores.
Frequently Asked Questions
Do I need to create an account?
No. There is no sign-up page, no login screen, no password and no email address. The app never asks you to identify yourself, and this website has no account area — if a link brought you here looking for one, it does not exist.
Is there a web version or a desktop app?
No. Kokoro Nikki is an iOS and Android app only. kokoro-nikki.com is the site that documents it; entries are written in the app, on the phone.
Which app is it, exactly?
Kokoro Nikki, also written 心の日記, published by Moreno Preto. On iOS: https://apps.apple.com/us/app/kokoro-nikki-ai-diary/id6759742651. On Android: https://play.google.com/store/apps/details?id=com.cre8labs.kokorononikki. Other diary apps use similar names; those two listings are the only ones that are ours.
How do I start the free trial?
From inside the app, through the App Store or Google Play. The 7-day trial applies to the annual plan and requires a payment method. The monthly plan is a direct purchase without a trial.
How do I cancel?
From your store subscription settings — App Store on iOS, Google Play on Android — at any time. You keep access until the end of the paid period, and your existing entries stay readable afterwards.
How do I move my journal to a new phone?
The entries do not travel by themselves. There is no cloud sync and no account holding them, so a new phone starts empty. Export from Settings before you leave the old phone: you get your whole journal as one Markdown file with a JSON block inside. The app cannot read that file back in, so treat it as an archive to keep, print or take elsewhere — not as a restore.
Start writing the story of your heart today.
7 days free on the annual plan. Payment method required. Cancel anytime.