use the below link to sign up N26 online app banking.
After they make a purchase of at least €50 using their Mastercard, we’ll deposit €50 into your account, and credit €50 back to your friend!
You will receive your cash reward after your referred friend opens an account with N26 and spends €50 or more with their card. Full T&Cs are available here. This two-way reward is only valid if your friend successfully signs up between 07 July - 31 July 2021