What is a use case? I am contemplating a more advanced excel-like app with separated flows for data acquisition (i.e. pulls via api), data management (tables, f

What is a use case? I am contemplating a more advanced excel-like app with separated flows for data acquisition (i.e. pulls via api), data management (tables, formulas, slicing) and view (graphing, input forms, buttons). I wonder if there would be a market for that and how to validate such idea…