Thank you for reaching out to the PowerSchool Community for assistance!
The grades, grading terms, GPAs, meal balance, and various other features that display on the mobile app are configured on a school by school basis by your school district’s PowerSchool administrators.
As features are displayed on a schoolwide basis, your school makes changes per their assessment of the school’s needs. Your school district’s PowerSchool administrators can contact support directly if further assistance is needed to make changes.
It sounds like this feature is not set to be displayed in the mobile settings for your school. Please feel free to share this information with your school if you believe they are not aware.