There are various schemes for outputting the data, by setting the appropriate configuration for the app.
The output schemes are either By Row, By Worksheet, or By Workbook.

There are a few features to note about the app:

Data can be output as JSON, along with the ability save datasets as JSON.
The number of rows or worksheets of data output are tracked with a count on a private data key. See documentation for details
There is an option to allow or disallow empty cells in the dataset output. If the option Allow Empty Cells is set to No, the entire row that the empty cell is found in will be excluded from the dataset output.
If Allow Empty Cells is set to Yes, a empty node will be generated in the dataset output.
By default empty rows are excluded from the dataset output
There is the ability to choose which line a header row is found in with the Header Row Is Elsewhere option set. This then allows the ability to designate where the data to be parsed starts at. In this scenario if the data to be parsed ends at a certain row then this can be designated with the option Specify if data ends at a specific row set to Yes, with the number of the row the data ends at specified at the option Row data to be parsed ends at.