Using Custodia
Everything the Mac app does, in the order you are likely to need it.
First launch
Set a master password of at least eight characters. Custodia shows a strength meter as you type. Write it down somewhere safe before you go any further. There is no recovery — if it is lost, so is everything you put in the vault.
Moving from another Mac or an iPhone? Choose Restore from Backup… on that
screen instead and pick your .custodiabackup file.
Adding things
A file or folder
Click Add to Vault and pick from disk, or drag files and folders onto the window. The original is moved into the vault, not copied, so it leaves its old location entirely.
From Finder's right-click menu
Right-click any file or folder in Finder and choose Lock with Custodia — under Quick Actions or Services, depending on how many you have. If the vault is locked, Custodia asks for your master password, moves the items in, and locks again afterward; if it is already open, it asks you to confirm.
Apps
Apps can't go in the vault. Custodia runs in the App Sandbox, and macOS won't launch an app that a sandboxed app has stored, so an app that went in would never run again. Custodia refuses apps, and folders that contain one, and tells you which.
Working with what's inside
Double-click any row. Files open in their usual app and folders open in Finder, from a private decrypted copy that only exists while the vault is open. Edit and save as usual: when the vault locks, your changes are encrypted back in and the copy is erased.
Rename
Right-click a row, or open the Actions menu, and choose Rename… — the extension is preserved for you, so a rename can never break how an item opens.
Restore, or move out
Restore to Original Location… puts an item back where it came from. Custodia records each item's origin in its encrypted manifest and opens a save panel on that folder with the name filled in; click Restore. macOS only lets a sandboxed app write where you have chosen, which is why it asks.
Move Out… is the same, for anywhere you like. Either way the item leaves the vault and becomes an ordinary file again. Neither ever overwrites something already there.
Delete
The vault holds the only copy of anything in it, so deleting erases the item from your Mac entirely — nothing is written back out first. This cannot be undone.
Locking
- Press ⌘L, or click Lock.
- Closing the window, or quitting, locks the vault as well.
- Auto-lock waits 1, 5 or 15 minutes, or never — set it from the gear menu. The timer follows activity in Custodia itself, so working in an opened item in another app does not hold it open. Changes you saved there are kept when it locks.
Backing up the vault
Gear menu → Back Up Vault…, then choose where to save. Custodia writes one
.custodiabackup file holding the vault exactly as it sits on disk — already
encrypted, and protected by the same master password.
To restore, choose Restore from Backup… on the setup screen of a fresh Custodia, on any Mac or iPhone, and enter the master password the backup was made with.
Worth doing before reinstalling macOS or removing the app. Keep the backup somewhere you trust: it is encrypted, but it is still a second copy, and losing the password loses it too.
Changing the master password
Gear menu → Change Password…. Only the key your password protects is re-wrapped, so it is instant and nothing needs to be moved out and back in.
Keeping it off the screen
From the gear menu, Custodia's window title can read Workspace or Math Quiz instead of its own name, so a shared screen or a passing glance at the window list gives nothing away. It changes what the window is called, nothing more — there is no decoy vault and no fake contents.