Ask your notes anything. Even we can't read the answer.
Prevon's AI runs on your device, right where the notes already live. Ask it something you half-remember and it answers from what you wrote. By default nothing you ask — or it answers — leaves the machine. No account, and the only key is yours.
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BIO 201 — exam 3 review
2:14 PMMitochondria → ATP production, Krebs cycle diagram. Prof said unit 4 is ~40% of the final, so start there.
Cell biology — week 3 lecture
YesterdayCristae fold up to pack more surface area for aerobic respiration.
Study group — Monday
MonPriya’s trick for remembering the mitochondria steps — ask her to redo that before the exam.
Reading — cellular respiration
Aug 30Glucose breaks down into roughly 32 ATP before a cell can use it.
4 notes match. Scroll, or open the top one.
Locked on your device
Only you hold the key — we can't read them
Write anything. It's encrypted before it leaves your hands.
01 · Write
Type like any notes app.
Class notes, group-project brain dump, 2am thoughts. Same box, same speed, no setup.
02 · Encrypt
It locks itself on your device.
Your notes get scrambled before they ever travel. We store the scramble, never the message.
03 · Ask
Your AI already read it — privately.
Search by meaning, not just keywords. Auto-filed as you write. None of it leaves your laptop or phone.
No account. No credit card. Free forever.
You never file anything. It does.
Every notes app makes you do the tidying — decide the folder, name it, drag it, remember to do it. Prevon takes that job away. Save a note and it is already where it belongs, before you think about it.
And it is honest about what it cannot do. Where the AI is not confident, it asks instead of guessing — and where nothing fits, it tells you plainly rather than dumping the note somewhere wrong.
BIO 201 — exam 3 review
The exam is mostly unit 4
Prof said unit 4 is ~40% of the final, so start there. Mitochondria → ATP production, Krebs cycle diagram.
“Don’t memorise the diagram — explain it out loud once and it sticks.”
— office hours, Thursday
Write, or press “/” for commands
It files as you save.
Write a note, save it, and it lands in the right folder — no prompt, no naming, no dragging. On by default; turn it off whenever you like.
It only guesses when it’s sure.
Close match, it files it. Vague match, it shows you the options and waits. No match at all, it says so and files nothing — it never invents a folder to look clever.
The decision never leaves your machine.
The model that reads your note runs on your own device. Your text is not uploaded to make the decision, and there is no server that could make it for you.
An AI that works for you. Not on you.
Most AI notebooks send your notes to a server. Prevon's AI runs on your device — it searches, sorts, and answers without your notes ever going anywhere.
It understands, not just stores.
Auto-filed into the right folder as you write. Search matches exact words and what you meant, together — not one or the other.
It asks before it acts.
Nothing is ever deleted without asking. Sort a note into a folder as you write — that part is instant. Anything bigger, like re-filing or merging, waits for your yes, and every action it takes is logged where you can see it.
Your notes never go to a server to be understood.
The AI that reads and organizes your notes runs on your own device, not in our cloud. Nothing to upload, nothing sitting on someone else’s machine. Want zero network of any kind? Turn on Air-Gap Mode and it blocks every outbound connection the app can make — including the device-to-device sync path.
What it does on its own — and what it doesn't
All of this runs on your device. There is no cloud AI in this build, even if you paste in your own API key.
- Files each note into a folder as you save it — decided on-device, no prompt.
- Writes a short summary for any note that doesn’t have one, and refreshes it when the note changes.
- Suggests a better folder when a note has outgrown the old one. You confirm it.
- Groups loose notes into folders and names them — only after you approve the set.
What it doesn't do: no AI renames your notes behind your back (there is a button if you want a title suggested). No auto-tagging, and it won't invent links between notes you didn't make yourself.
Your notes are yours. Only you hold the key — not us, not anyone.
Not a policy promise — a structural one. Encryption happens on your device, with a key only you hold.
100%
encrypted on your device
0
times we can read your notes
0
trackers, analytics or ads
1
key, and it never leaves you
When a breach happens, it happens to plaintext. Ours isn't. Lose your Recovery Seed and we cannot recover your vault — that's not a flaw, it's the whole point.
Free forever. $4/month for sync.
The whole app — encrypted notes, on-device AI — is free with no account. You only pay if you want your notes synced between devices.
Free
$0
No account, no card, no catch. The full vault.
Ghost Sync
$4/month
Sync between your devices that stays locked the whole way. Ships after the beta.
Check it yourself. The code doesn’t ask for trust.
Built to be attacked
The beta is the security test. Every seat goes to someone whose job is to try to break the vault — and what they find gets fixed before it ships to anyone else.
Nothing about you leaves the device
No account, no trackers, no analytics. The server never holds a key that opens your notes.
You can check the claims
A PGP-signed warrant canary, a public key to verify it, and an open credit page for security reports.
Start simple. Your phrase is always the way back in.
You don't need to be a spy to use Prevon. Open it with Face ID — and your 12-word Recovery Seed gets you back in if you ever lose the device.
Quick unlock
EverydayPIN or biometric
Face ID or fingerprint to open the app. Fast, no retyping.
Full unlock
RecoveryYour 12-word Seed
Your Recovery Seed opens the vault on a new device, or after a reset. Only you hold it.
Step-up check
Opt-inRe-auth to change
Turn on a re-auth gate so sensitive changes need your phrase again, even on an unlocked device.
Behind the build.
Free forever. No account. No catch.
The full vault — encrypted, AI-powered, yours. Nothing you write has a path off your device.
No card. No signup. Nothing to cancel.