What are Youtubers using to scan the barcodes from their Amazon packages

I noticed when Youtubers open giant mystery pallets of amazon products they scan the barcode using an app that generates the price it sells for and sometimes the rank of the product. I have also seen Youtubers at stores doing arbritrage using a similar app to see if an item is worth reselling. Do any of you know what app they could be using? I have a simple Amazon individual seller account and have never done FBA.