Can a customer scan a card using the Joyn Business App Lite?

Follow

Yes, absolutely. Once you've entered the points, you'll see a screen with a QR code. If your customer has a smartphone, he can use it to scan this QR code using the Joyn app on his smartphone. If your customer doesn't have a smartphone, tap the 'Scan a card' button and scan your customer's card using the camera on the back side of your Android device.
If you prefer using the camera on the front side of your device, tap the blue button in the bottom right corner of your screen to swap cameras.