User guide
Sharing
How to let one person see one part of your inventory — and why you read six digits aloud to do it.
Screenshots are from the iPhone app. The Android app has the same features, drawn in Android's own style.
What gets shared
What you share is an Abditum — a container — not your account and not your inventory. You can share as many containers as you like, and each one with as many people as you like; the containers you have not shared stay private, and private Abdita are never transmitted at all, not even encrypted.
People are added one at a time: each person joins through their own ceremony, so the answer to "who can see this?" is always a list you built deliberately, one decision per name.
Typical use: a spouse who should see the household holdings, a business partner in one specific box, an heir who should have visibility now rather than a surprise later, an accountant who needs to see but not touch.
Permissions
| Label | Can do |
|---|---|
| Admin | The person who shared it. Adds and removes people, and ends the sharing. |
| Can edit | See everything in the Abditum, add holdings, change them, delete them. |
| View only | See everything in the Abditum. No adding, editing, or deleting — the buttons are not there. |
Where an action is unavailable to you, the app says why rather than silently hiding it.
Setting up a sharing
You do this together — in person, or on a video call. Both phones need internet, and the sharing completes the next time each phone is online.
- You open the Abditum you want to share and tap Add a person. They open Abdita ▸ Join a sharing.
- Both phones show a QR code straight away. Point each phone's camera at the other's code — in either order. There are no next buttons; each step greys out as it completes.
- Both phones now display the same six digits. Read them to each other out loud. If they match, each of you taps These match. If they do not, stop — tap "They don't match" and start over.
- Done. The Abditum appears on their device once both phones have synced.
Why the six digits matter
They are the security of the whole exchange. The two phones agree on a key by showing each other public values, and those six digits are a fingerprint of everything they exchanged. If somebody were sitting in the middle intercepting the exchange, the two phones would compute different digits — and you would catch it by reading them aloud.
This is why the app asks for a deliberate tap instead of proceeding on its own: the check only works if a human actually does it. It is the same idea behind the safety numbers in secure messengers.
The codes on screen contain no secret — they are safe to photograph. The key itself is delivered separately, sealed so that only the other person's device can open it. That is why sharing over a video call is fine; the picture on the screen is not the secret.
Seeing who has access
More ▸ Users lists everyone you share anything with, and each Abditum's own Access sheet lists the people on that one. Shared Abdita are badged in your lists so you always know which of your containers other eyes are on.
Adding someone you have already shared with
Only the first exchange with a new person needs the ceremony. Once your devices know each other, adding that person to another Abditum takes no meeting and no scanning — the key travels sealed to their device, and neither we nor anyone else can open it in transit.
Removing someone, and ending a sharing
Remove a person from the Abditum's Access sheet, or from Users to remove them everywhere at once. Make private ends a sharing for everybody in one tap; removing the last person does the same thing.
Removal re-keys the Abditum, so the removed person cannot read anything you do from that point on.
What removal cannot do
It cannot make someone forget. Anything they could already see, they may have already read, photographed, or written down. Removal stops future access; it is not an undo. The same is true of moving a holding out of a shared Abditum — it takes effect going forward.
Limits
Sharing is part of Pro. There is no limit on how many Abdita you share, and each one holds up to 10 people including you.
That 10 is not a tier boundary we could lift by charging more — it is there because removing someone re-keys the container, and today every remaining person needs a fresh ceremony afterwards. Ten is the largest sharing where that afternoon is still a manageable one. When re-keying becomes invisible, the number goes up.
There is exactly one admin per shared Abditum, and admin cannot be transferred.