Absolutely! There are two ways to add a promotion/referral code to your account. Please note -- once a code has been added, it cannot be edited. Additionally, this can only be done from the web and not the mobile application.
When creating a new account, you're able to add your code during the account creation flow. Pictured below:
If you did not add the referral code during the sign up process, please submit a ticket and our team will assist you.