Why it exists
You have the ideas. You just can't get back to them when they matter.
Nemosine exists to reduce the cost of thinking the same thoughts again: finding what you wrote, connecting it, and picking it back up months later. You don't have to become a librarian for your own notes.
How it's made
- Write first, sort later: you don't pick a folder before you start typing. A note can be filed later, or never.
- Your device first: the app reads and writes a database on your device and keeps working with no connection. The network is optional.
- Encrypted before it leaves: when sync is on, notes are encrypted on your device with a key derived from a password we never receive.
- Yours to take with you: everything exports as Markdown.
Notes and folders
A note is one piece of writing. Folders hold notes and nest as deep as you want. Notes can link to each other, so something you wrote in March can sit next to what you're writing today.
Help when you ask for it
Nemosine doesn't write for you unless you ask. In the iPhone, iPad and Mac apps you can ask an AI that runs on your device about your own notes, search by meaning (on iOS 18 and macOS 15 or later), and record voice notes.
Privacy, specifically
Nemosine cannot read your synced notes. Content and attachments are encrypted on your device before upload, and the server holds encrypted rows plus the sync metadata needed to route them — account and device identifiers, row IDs, timestamps, versions and usage counters. Your sync password is separate from your login password, and we never receive it. The full list is in the privacy policy.
What we don't do yet: Nemosine doesn't encrypt the notes stored on your device itself, and it doesn't lock the app with Face ID or a passcode. Your device's own encryption protects those notes, so keep a passcode on it. The sensitive-content PIN hides notes but doesn't encrypt them. Section 6 of the privacy policy has the details.
Who we build for
People who think by writing: working through a decision, a project, a hard week, and coming back to it later.
Some of them keep notes that would hurt if they leaked: therapists thinking through a hard session, lawyers working a case, journalists keeping source notes, anyone keeping a private journal. They want help thinking across what they wrote without handing it to a cloud service. Nemosine is for that personal thinking. It is not a clinical-records or case-management system.
The company
Nemosine is made by Nemosine AS in Norway (organisation number 937 091 567). Write to us at support@nemosine.app or through the contact form.