In your admin dashboard, click on the Settings menu to reveal a drop-down menu. Next, click on the Delivery option and a Delivery Settings form with six tabs (Fields, Reasons, Recipients, Notes, POD and Webhook URL) will be shown.

Under the POD tab, switch on Allow drivers to select photos from photo gallery, click Save and you are done.

Your drivers will now be allowed to use photos from their photo gallery to submit POD.