To export your sales history from the app, follow these steps:
Tap the icon in the top left and from the menu select "Activity" and you will be presented with your sales history.
Tap the icon in the top right and you will be presented with checkboxes to select the time periods of sales data you wish to be exported. Once ready, tap the icon in the top right again.
A CSV file of the selected data is generated and you will be presented with share options available on your device. Select your preferred export method to complete the process.