You can “appify” a spreadsheet easily in Thunkable, meaning use a spreadsheet as a database for your app’s data. Check out the Tech Superstars tutorial as well as the Meet My Classmates tutorial (classic UI).
You can also perform processing on the data in a spreadsheet. Check out this Music rating sample that averages the numbers from a spreadsheet column and this Oscar winners sample that shows how to filter spreadsheet data (e.g., show only Spanish films).
Click on the pics below to get to the source code for the apps.