I agree this would better packaged as a phone app. There are several apps out there that scan barcodes to detect a product. Amazon's app is an example. There is a price comparison website in Brazil (buscapé) that also has an app which does that. I don't believe the camera needs to be that accurate, as I have used them on several Android devices, from lower- to higher-end phones.
For using the barcode, a dedicated scanner is clearly better (especially faster). Reading the barcode with the camera is reliable as a fallback, but many products have packaging that should be possible to recognize directly with a camera, especially for items you commonly buy.
I don't know, maybe that's overkill and just pointing the barcode at a dedicated reader is actually the better experience.
