Set up collaboration

Collaboration lets two or more devices work on the same book at the same time — you and a partner, or your own phone and laptop. Everyone sees each other's transactions within seconds, and everyone can keep working offline; changes merge when the devices reconnect.

This is different from Cloud sync. Cloud sync backs your book up to your storage. Collaboration shares one live book between people. A book does one or the other, never both.

What sharing a book means

The other device gets a full copy of the book — every account, every transaction, the balances, the lot. It isn't a read-only view and it isn't limited to part of the book. Share a book only with someone you'd hand your whole ledger to.

They can add, edit and delete anything. They can't back up or export the book, and they can't invite or remove devices; those stay with the owner (see below).

The password is the key

The book password does two jobs: it unlocks the book on your device, and it encrypts everything the devices exchange. The sync service in the middle only ever sees ciphertext.

That has three consequences worth knowing before you start:

• Anyone holding the invite link and the password can read the whole book. Send them by different routes — the link in a message, the password spoken aloud or in a separate app.
• The password is never in the link, so we can't pass it along for you. You have to tell the other person yourself.
• If everyone who knows the password forgets it, the book cannot be recovered. Not by us, not by anyone.

Creating an invite

Type or confirm the book password, then tap Create invite. Preparing the keys takes a few seconds the first time.

You get a QR code and a link, and they are the same thing — the other device can scan the code or open the link. Use Share link to send it, or Copy link to paste it somewhere.

The link is good for one hour and for one device. Once someone joins with it, it's spent. Need another? Tap Create a new invite — that's also the fix if a join goes wrong.

Where will they open this invite? picks which app the link opens on the other end: Web for the browser version, In the app for the installed phone app. If you're not sure, leave it on Web — that link opens in a browser anywhere.

Approving the other device

Joining is two-sided on purpose. When the other device asks to join, a prompt appears on your device asking you to approve it. Nothing syncs until you do.

You don't have to sit on this screen waiting — the prompt finds you anywhere in the app for the next 15 minutes, and after that whenever you reopen it. Approve waiting devices does the same check by hand if you missed the prompt.

If a device tried to join with the wrong password it is refused automatically, and you'll be told. They can try again on the same invite; a wrong password doesn't burn it.

You are the owner

The device that creates the first invite becomes the book's owner. Only an owner can invite new devices or remove existing ones.

Owner-ness lives in a key stored on this device — it isn't tied to an account, so there's nothing for us to reset. If this device is lost and you haven't saved a recovery code, nobody can ever administer this book again. Save one now: Manage devices → Owner access.

Sync service (advanced)

Devices exchange their encrypted changes through a small relay service. By default that's the one we run, and there is nothing to configure. It stores ciphertext and cannot read your book.

Under Advanced settings you can point the book at your own relay instead, and supply an enrolment token if that relay requires one. Both are for self-hosting; leave them alone otherwise. Everyone on a book must use the same relay.

Tips

• Have the other person nearby the first time. Pairing takes under a minute when both devices are awake.
• Take a backup before you start (More → Backup). Sharing a book can't corrupt it, but a copy costs nothing.
• Turning on collaboration switches this book off Cloud sync. Your existing cloud copy stays where it is; it just stops receiving updates.
• Changing the book password later asks every other device for the new one, and you'll have to tell them what it is.