You can easily share one or multiple accounts in Bulder. Either start the sharing directly from the account you wish to share, or tap on "Bulder" -> "Shared economy".
Shared economy
To share an account, do the following:
Tap on Bulder
Tap on Shared economy
Add someone you want to share with.
Enter their social security number
Choose which accounts you wish to share.
The person you wish to share an account with has to be a customer of Bulder.
Edit shared economy
You can edit shared accounts from Shared economy. Here you can add or remove shared access.