What I Learned Building an Android QR & Barcode Scanner

Building a QR and barcode scanner for Android taught me that the hardest part is not simply detecting a code. The real challenge is turning scanning into a useful workflow. For my project, I wanted the app to do more than open a link after scanning. I wanted users to be able to keep scan history, organize results, work with QR codes and barcodes, and use the scanner as a practical productivity tool. The stack The Android app is built with Kotlin and uses modern Android components. For camera access, I use CameraX. For code detection, I use ML Kit because it provides reliable support for QR codes and multiple barcode formats. What became more complex than expected At first, scanning looks simple: Open the camera. Detect a code. Show the result. But once the app grows, many UX decisions appear. For example: How often should the same code be detected? Should the phone vibrate on every detection? How should scan history be organized? What happens when a barcode contains text instead of only numbers? How should users scan an image from the gallery? How do you make the camera interface fast without making it confusing? These details can have a bigger impact on the user experience than the scanner itself. QR codes and barcodes are not only for supermarkets One thing I wanted to avoid was designing the app as if barcodes were only product numbers. Barcode formats are also used in logistics, manufacturing, inventory systems and other workflows. That means the app should treat scanned data flexibly instead of assuming every result is just a numeric product ID. Building around the scanner The project gradually evolved into a larger tool. Instead of treating each scan as something temporary, the idea is to let users keep and organize useful information after scanning. This is also why I am experimenting with productivity features around projects and data export. What I learned The main lesson was simple: A feature can work technically and still need a lot of work before it feels useful. Camera performance, feedback, organization and small interface decisions all matter. I am continuing to develop Android tools under NEVIRAX. You can find the project and more technology-related content here: https://nevirax.com