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Pro Keeps history of scanned codes
You can keep a history of every code scanned, or just the ones that you've scanned more than once.
Pro Can generate QR codes for apps, bookmarks, contacts, and clipboard data
Pro Auto-use Flash
Can turn on from settings to turn on the Flash light automatically.
Pro Supports Wi-Fi QR codes
Can be generated on https://zxing.appspot.com/generator/
Pro Open source
Barcode Scanner is an open source project and the Github repository can be seen here.