How do you select multiple files on Android?

To select multiple files press on as many files as you want to select and check marks will appear over all of the selected files. OR you press the More options menu icon in the upper right corner of the screen and press Select.

How do you shift a select?

Scroll to the last item in the section, hold down the “Shift” key and click the item. Shift-Click selects the first item, last item and all items in between. Use the Ctrl key to select additional items outside of the consecutive group, then click the button to process the selections you highlighted.