The summary bar provides different types of summarizations of all the cell values in a given field. To see the summary bar for the fields in a table, scroll downward on the table until you see the field header bar expand to show the summary bar. By default, the summary function for each numeric field is Sum, and the summary function for non-numeric fields is blank.

You can configure which summary function appears in each field in the summary bar. Tap on a specific field to bring up the field configuration menu. From here, you should see an option to Choose summary function.

Tapping this option will bring up a list of the available summary functions available. The types of summary functions available will depend on the type of field.