You can invite any Qube user to join your account. They must be at least 18 years old and have an active Qube account. When you invite another user to join your account, you will have access to the same qubes, funds, and ACH information.
The primary account holder is responsible for all transactions/actions within the app made by the secondary user. When the accounts are joined, there will be one account number with two separate debit cards.