There is a phone app, that pretty much allows you phone to work like the scanner gun. I’ve used it before and it works fine, but my phone’s camera is not as good as the guns at scanning barcodes.

Also, as much as I realize I am trading privacy for control, I figure there’s no need to have the grocery store’s app living on my phone, when it is just as easy for me to use the dedicated device they provide in-store.