WhenToHelp Lite is set to let helpers trade or pick up shifts "at will" without needing coordinator approval. If you have a paid subscription you have the option to require coordinator approval for all trade and pick up requests (which can be changed in the SETTINGS>Global Helper Permissions page). If you require Coordinator approval for trades and/or pickups, the Trades>Trades Awaiting Approval page will show you the shifts awaiting Coordinator Approval and also the shifts that are in process between helpers and an awaiting helper to agree. How helpers can use the Tradeboard is controlled from the SETTINGS>Global Helper Permissions page.
You also can see which shifts are on the Tradeboard or pending Coordinator Approval on the By Helper Schedule View, where a Tradeboard icon will appear next to the shift.