A phone screen round is oftentimes when a recruiter has a 1:1 conversation with you about a role you applied for. These are often 15-20 minutes in length.
It often includes:
Logistical information
These aren't so much get to know you as just checking off and confirming information.
Behavioral questions
This is to get a better sense of how you operate and/or otherwise under working with others and different type settings.
Company questions
This is to get a sense of why you like this company compared to applying to another.
Technical questions
This wouldn't be as technical as a portfolio review round, but sometimes they might ask your familiarity with design/research tools.