This app is designed to calculate college GPA's. The calculator is based off of a 4.0 scale where A = 4.0, A- = 3.7, B+ = 3.3, B = 3.0 and so on. At the main window you enter how many courses you are taking and the application will open a new window to calculate your GPA. You are able to select anywhere between 4 and 9 courses. If you are taking fewer than 4 courses the calculator will still work, you just enter the information for the courses that you have.