An extremely fast QR Code Scanner app, which I believe is nowadays kind of essential for all mobile devices. Try this app and help yourself out ;)
One of the first simple apps I created while on my journey to learn flutter.
https://github.com/ishandeveloper/QR-Scanner-App/raw/master/app.apk
git clone https://github.com/ishandeveloper/QR-Scanner-App.git
cd \QR-Scanner-App
flutter run
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