The Pick List functions in the mobile app are very similar to the functions in the desktop app. Simply touch the button that says pick list to move on to the next screen. 

In the next screen you can load your current orders. Tapping the Load button will populate your current list of orders, the screenshot below illustrates the view after loading. Touching and holding a finger on the item pulls up a menu which can give you item details, scan location, and the option to set the item as picked or unpicked. Simply tapping the item with the REMOVE box unchecked will consider the item picked and it will change color from red to green. If the box is checked it will remove the item from view when tapped to help consolidate completed work for a clearer view.