To enable device barcode as a device scanner, you need to enable it first from the settings then you can use camera as a barcode.
#1 : Click on Twirll logo on the top left of the page that will open up the options menu
#2 : Click on settings from the options menu
Locate “Barcode Scanner Settings” below the printer selection menu
#1 : Enable this option if you are using PoS system through the device.
#2 : If you have an external barcode scanner then select this to proceed.
#3 : Select this if you don’t wish to use any barcode scanner.
Once “Using device camera as a barcode scanner” is selected then a scan button will appear in PoS header clicking on which will enable device camera which will be used for adding items into cart