Several libraries
You can have as many libraries as you like on the same device. Each one is a separate list, with its own books, its own people and its own devices. It is useful for not mixing things that do not go together:
- the one for home, which you share with your family;
- the one for the role-playing or reading club, which you share with other people;
- yours, which you do not share with anyone.
Each library is shared separately. You can give a device the home library and not the club’s.
The people are also specific to each library, and so is what each one can do (their role). Someone can be in charge at “Home” and only look at “Book club”. It is explained in People and permissions.
The words work, details and copy are used here. They are explained in Three words the app uses.
Create a library
Section titled “Create a library”- Tap the name of the library shown at the top. On the phone it is in the middle. On the computer, it is the box at the top left. “Your libraries” opens.
- Tap “New library”.
- Type the name (“Home”, “Role-playing club”, “Office”…).
- Tap “Create”. On the computer, the button is called “Create and open”.
The new library is empty, and it becomes the one you use.
Two libraries cannot have the same name. If you already have one with that name, the app tells you and offers to open the one that already exists.
Maybe, instead of creating one, you want to use the library another person has shared with you. The same box offers this: “Was it shared with you? Join from Devices”. This is done by pairing, which means connecting two devices so that they pass changes to each other. It is explained in Share at home.
Switch from one to another
Section titled “Switch from one to another”In “Your libraries”, tap the one you want.
You will see how many things each one has. The one you are using has a check mark (✓).
The gear icon on each row opens that library’s “Library settings”.
Search all
Section titled “Search all”The search box has two options:
- “In Home”: searches only the library you are in. The name of your library appears there, which may be another name.
- “In all”: searches all your libraries.
With “In all”, the results are grouped by library. Tapping one opens it in its own library (“Opens in…”).
It is useful, for example, to know whether you already have something before you buy it. In “Do I have it?” the same thing happens: it tells you “You have it in 2 of your 3 libraries”.
Move a thing to another library
Section titled “Move a thing to another library”- Open its details (its page).
- Tap “More options” (the three dots) and choose “Move to another library”.
- Choose the destination library.
- Tap “Move to…” followed by the name.
This option only appears if you have more than one library and you can delete that thing in the current one. In a shared library, that depends on your role (see People and permissions).
What happens:
- The thing moves with its copies, genres, tags, notes and cover. It stops being in the original library.
- If the destination library already had that book (the same ISBN, the number next to the barcode), its copies are added to it.
- Your own marks do not move: whether you have read it, your stars, your favorite and “I want it”. They are explained in Your own: to read, reading, read, stars, favorites and “I want it”.
- The series it belonged to does not move either.
In the destination library you have to note your marks and the series again.
Remove it from this device, leave it, duplicate it or delete it
Section titled “Remove it from this device, leave it, duplicate it or delete it”All four are in “Library settings”, at the very bottom.
“Remove from this device”
Section titled ““Remove from this device””The library disappears from this device. The other devices keep it, and so does your cloud account, if it has it.
This only works if the library is also somewhere else: on another paired device, or in your account’s cloud. With the cloud, the app asks it at that moment: with no connection, or if the cloud does not have it, the library counts as being only on this device, and removing it would lose it. If you administer the library, the app takes you to “Delete library”, where you can save a backup first. If you do not, it offers to save a backup.
To have it back:
- If it is in your account’s cloud, use “Bring down again” in “Sharing and devices” (see The cloud).
- If not, you must pair again with one of the devices that have it.
“Leave the library”
Section titled ““Leave the library””This is different from “Remove from this device”. Here you lose access to the library: it disappears from all your devices and from your cloud account. It is what you do when you leave a family or a club.
- Your books stay in the library, in your name. Nothing of yours is deleted.
- Only whoever administers the library decides whether you come back: they have to give you access again and link a device of yours. This library does not appear under “Removed from this device”, because you did not remove it: you withdrew.
- Anyone can use it, reader, editor or administrator. The only person who administers a library cannot leave: the app asks them to name another administrator first, or to delete the library.
- It works the same without an account, on the home network alone.
- Your device does not delete the library at that very moment: the exit has to reach another device first (through the cloud or the home network). When it does, the library disappears from yours. If there is nobody for it to reach, the app tells you it will disappear as soon as it syncs.
- It is not deleting your account. Leaving a library does not touch your cloud account; for that, see The cloud.
“Delete library”
Section titled ““Delete library””It is deleted on all the devices that have it, with all its things, copies and history. It cannot be undone. Only people who administer the library see this option; everyone else sees “Remove from this device”.
The app tells you how many things will go and, if the library is shared, on which devices.
First, it offers to save a backup: “Save a backup of…”. You can restore it later. If you do not want one, tap “Delete without backup”. How backups are made and recovered is explained in Backups, export and import.
If you delete the only library you had, the app creates an empty one.
“Duplicate as a new library”
Section titled ““Duplicate as a new library””This option only appears in the libraries you do not administer. Administering a library means being able to change it and give permissions to others.
It is the last resort, for when nobody can administer a library. For example, because its only administrator lost their only device.
It creates a new library with everything you had noted: the people, and each person’s marks. You administer it.
The copy does not have each person’s permissions, nor the devices you shared it with, nor the history of changes. The others will have to connect again to the new one (by pairing). The original library does not change.
The cloud, library by library
Section titled “The cloud, library by library”If you have an account, you can upload a library to the cloud, which means keeping it on the internet too, in your account. It is a decision you make for each library. What you do not upload stays on your devices. It is explained in The cloud.
© 2026 Kosmotheka
Kosmotheka is free software: the app and the server are under the AGPL-3.0-or-later, and the operation spec is under the MIT licence. The name and the logo are not covered by the licence.
kosmotheka.com · Trademark policy · Privacy policy · info@kosmotheka.com