Tune each vault to your needs
Set a tight zone for high-security items or a more forgiving one for convenience. The radius is enforced with the device’s reported GPS accuracy added in, so normal GPS jitter doesn’t lock you out.
Vaults must be at least 100 meters apart so locations stay unambiguous.
For hidden vaults you also pick the pool size and how many vaults to divide it into, choose this before creating your first hidden vault, as it can’t be changed afterward without wiping them.