Faster scan

In previous articles, we’ve seen how optimizing the contents and the resolution of the QR code improves the user experience, by making the scan step faster.

Likewise, the QR code decoder in the mobile apps matters a great deal. We observed that this step was consistently faster on iOS devices than on Android.

It typically takes 2 seconds for the iPhone user to aim at the QR code and have it successfully parsed by the iPhone app. The Apple hardware and the AVFoundation framework are doing a great job here.

The Android app was using an old version of the ZXing decoder library. We replaced it with the ML Kit scanner and released our Android app version 1.2.2605c. This simple change saved 1 second on each scan!

Scan speed in the iOS app and the Android app
Scan duration in milliseconds: smaller is better

Including the ML Kit module increased the Android app size by 3 MB. This is a great trade-off.