For the scan to work, you must make sure:
1) That you've authorized access to the camera. If not, you'll need to change this in your phone's settings:
- On iOS, go to "Settings", click on "Yuka" and check "Camera".
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- On Android, go to "Settings", click on "Apps", then on "Yuka" and finally on "Permissions". Then check "Camera".
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2) That you've authorized the application to use cellular data. If not, you'll need to change this in your phone's settings:
- On iOS, go to "Settings", click on "Yuka" and check "Cellular Data".
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- On Android, go to "Settings", click on "Connections", then on "Data Usage". Then check "Mobile Data".
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3) That you have an internet connection, which is not necessarily the case in all supermarkets.