Question 1

Is it actually free?

Accepted Answer

Yes. The whole app is free forever, offline, no account. Ghost Sync is the only thing that costs money, and it's optional.

Question 2

What's the catch?

Accepted Answer

There isn't one. We don't sell your data because we can't read it. We make money from the people who pay for sync.

Question 3

Can I use Prevon without creating an account?

Accepted Answer

Yes. The Free tier works completely offline — no account, no cloud sync, no data leaving your device. Everything is stored locally and locked with keys that never leave your machine. Ghost Sync adds optional encrypted cloud sync for users who want to access their notes across multiple devices.

Question 4

What happens if I want to leave Prevon?

Accepted Answer

Your data is yours. You can export your vault as an encrypted backup file at any time — no lock-in, no proprietary silo. If you cancel Ghost Sync, your local app continues working with full functionality; you just lose cloud sync access. Your local notes are never touched. Synced copies on our servers expire on their own if the subscription stops renewing — see the Ghost Sync page for how that works.

Question 5

What happens if I forget my Recovery Seed?

Accepted Answer

We cannot recover your Recovery Seed — we don't have it. This is by design. If we could recover it, so could anyone who compromised our systems. We recommend writing down your Recovery Seed and storing it securely. The Free tier works entirely offline so you only need the seed to restore your vault.

Question 6

Does Prevon sell my data?

Accepted Answer

We don't have your data to sell. Your notes are locked locally with keys that never leave your device. We don't use analytics trackers, don't collect usage data, and don't log what you write. Our business model is subscription-based, not data-based.

Question 7

How do you make money without selling my data?

Accepted Answer

We sell the optional cloud sync service, not what's inside it. Ghost Sync subscribers pay for encrypted sync across devices — a real service with real infrastructure costs. Our business model depends on protecting your data, not exposing it.

Question 8

How does the encryption work in Prevon?

Accepted Answer

Your notes are locked on your device before they are synced anywhere. The keys never leave your devices — not even to us. This means that even if someone gained access to our servers, they would see only scrambled files with no way to unlock them without your keys.

Question 9

Where does the AI run — on your servers or my device?

Accepted Answer

On your device, by default and for everything that touches your vault: auto-filing, search by meaning (exact match and meaning, together), and the AI can actually edit your notes — essentially anything you can do to a note, the AI can do too, under the same permission rules. Your note content is never sent to an external AI service. If you want, you can separately opt into a cloud AI provider for a more powerful conversational assistant — that channel only ever sees what you type directly to it, never your notes.

Question 10

What encryption does Prevon use?

Accepted Answer

Your vault is locked with keys derived from your 12-word Recovery Seed, and the key-making step is deliberately expensive — enough to make guessing your password by brute force practically impossible. The actual encryption is XChaCha20-Poly1305, the same authenticated cipher family used by Signal and libsodium.

Question 11

How does end-to-end encrypted sync work?

Accepted Answer

When you enable cloud sync, your notes are locked on your device before upload and unlocked only on your trusted devices. Our sync servers store only the scrambled data — we cannot read your notes, cannot access your content, and cannot help anyone else read them either.

Question 12

Why don't you know how many notes I have, or who I am?

Accepted Answer

Because we designed it that way. Your notes are stored with no folders, no usernames, and no account tied to them on our servers — only your 12-word key can find and unlock what's yours.

Question 13

Is Prevon's security design documented?

Accepted Answer

Yes. We publish detailed documentation about how our encryption works, how keys are managed, and how the security model holds up. We welcome security researchers to review our implementation.

Question 14

What happens to my notes if Prevon goes out of business?

Accepted Answer

Nothing happens to them, because they were never dependent on us. The Free tier runs entirely on your device — if our servers disappeared tomorrow, your vault and on-device AI keep working exactly as before. Ghost Sync users would lose sync, but their local vault stays fully intact and readable.

Question 15

How do I know you're not just saying all this?

Accepted Answer

Don't take our word for it. The whole design is documented on the Security page (/trust) — not vague reassurance, the actual design, down to the algorithms and the source files that prove them. We welcome independent security researchers to try to break it, and anyone who finds and responsibly discloses a real issue gets permanent public credit on our Hall of Fame page (/hall-of-fame).

Question 16

Does paying for Ghost Sync reveal my identity?

Accepted Answer

To Stripe, yes — processing a subscription means Stripe necessarily sees your card and billing details, the same as it would for any company you pay online. That is unavoidable and we won't pretend otherwise. Your vault is a fully separate system, not linked to your billing identity in any way — no name, email, or account identifier ties the two together. Being a paying customer tells us someone with your card pays us $4 a month. It does not tell us which vault is yours or what's in it — only your Recovery Seed can compute that, and we never have it.

Question 17

If cloud sync is encrypted, why not just store everything in one folder per account like everyone else?

Accepted Answer

Because encryption only protects what's inside a file — it doesn't hide who it belongs to. A folder labeled with your account still tells anyone with server access exactly where to look, even if they can't read the contents. Prevon stores synced notes without any account folder or user ID attached to them at all, so there's no label to find in the first place — only your Recovery Seed can compute which pieces are yours.

Question 18

Does a backup or sync object reveal how much I write, or how often?

Accepted Answer

We treat that as a real privacy leak worth closing, not an acceptable side effect of encryption. Sync and backup objects are designed to be padded to a small set of standard sizes before encryption, so a short note and a long journal entry look the same from the outside. We're upfront that this hardening is actively rolling out rather than a finished, audited guarantee today — see our blog for the current state.

Question 19

What happens if you're legally compelled to hand over data?

Accepted Answer

We would comply with valid legal process, as any company must — but we can't read your notes, so there's nothing readable in our possession to hand over. We also maintain a warrant canary (/warrant-canary), a scheduled statement confirming we haven't received certain categories of legal demand.

Platforms
	Free	Ghost Sync
	Apply for the beta
Get started	Apply for the beta	See how it will work
Windows	Included in Free	Included in Ghost Sync
macOS	Included in Free	Included in Ghost Sync
Linux	Included in Free	Included in Ghost Sync
Android	Included in Free	Included in Ghost Sync
iOS	Included in Free	Included in Ghost Sync
Security
Local encryption	Included in Free	Included in Ghost Sync
The AI runs on your device	Included in Free	Included in Ghost Sync
We can’t read your notes	Included in Free	Included in Ghost Sync
PIN / biometric quick unlock	Included in Free	Included in Ghost Sync
Sync
Cloud sync	Not included in Free	Included in Ghost Sync
P2P device pairing	Not included in Free	Included in Ghost Sync
Cross-device encryption	Not included in Free	Included in Ghost Sync
Data
Manual encrypted vault backup	Included in Free	Included in Ghost Sync
Support
Documentation	Included in Free	Included in Ghost Sync

Feature	P Prevon	N Notion	K Google Keep	Apple Notes	··· Others
We cannot read your notes
On-device AI processing
No account required
Sync that stays locked in transit
Device-to-device sync, no cloud in the middle
No note content sent to a cloud AI
No content used to train third-party AI

Free, or $4 a month. That’s it.

What's included:

What's included:

Nothing to steal. Nothing to hand over.

No account to breach

Nothing readable, ever

No keys to hand over

Sync across devices without handing anyone an address.

Encrypted before it ever leaves your device

No account folder on the server

Billing is separate from your vault

Your local vault never depends on the cloud

Your vault, your terms.

Not all privacy tools are the same

Product

Security

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