We all know retailers use barcodes to move shoppers through the checkout quickly, but shoppers also can use them to find the best deals on Black Friday and beyond. All it takes is your smartphone’s camera – along with one of the following apps – and you’ll be virtually guaranteed to find the best deal. BuyVia compares prices at national and local outlets, even online sites like Amazon, to find the best deal. Set up the app and you get alerts for products when they go on sale – even help in finding them at the closest physical location. The app is free for Android and iOS and works with Apple…