I contributed to the development of a new web-based Point of Sale (POS) interface for Landbrugslotteriet, designed specifically for tablets and embedded within a custom Android application. The goal was to modernize the retail experience by delivering a reliable, touchscreen-optimized web app that could communicate seamlessly with the host Android OS and a customer-facing display.
The frontend was built using React and Redux, allowing for tight control over app state and user interaction. I worked on integrating the web layer with native Android APIs exposed to us by the host app. These APIs allowed us to trigger actions like printing receipts and receive real-time updates on hardware status—such as printer health or connectivity issues—directly from the tablet.
One of the more challenging parts was ensuring tight, bidirectional communication between the main POS interface and a secondary customer-facing display. These were separate browser contexts but shared state through a backend service and webhooks. This required setting up event-driven architecture that stayed in sync even under flaky network conditions.
The codebase was tested thoroughly using Cypress, covering both user flows and hardware interaction edge cases. We simulated hardware failures and verified how the UI responded in degraded modes. This project deepened my experience working with hybrid mobile-web setups, real-time state management, and integrating third-party native APIs in a controlled environment.
