React Native BLE PLX Mock Recorder

Lars Thorup explains a way to run fast, robust integration tests for React Native apps that communicate with Bluetooth devices. Instead of relying only on slow, fragile end-to-end tests or hand-written mocks that can drift from the real device protocol, the approach records real BLE traffic and replays it in Jest tests. A lightweight recorder app captures traffic on a phone with a physical device; developers then use those recordings to test app components on a computer in milliseconds. The talk also covers canonical device IDs and values, validating live device data, combining recordings with manual mocks, and making BLE recordings easier to read.

The conference talks show how React Native teams handle large codebases, code splitting, debugging, animation, security, testing, and real-time communication. Microsoft engineers present React Native Test App and rnx-kit check as tools for simplifying development across monorepos and aligning dependencies. Other speakers demonstrate Re.Pack for webpack-based code splitting, compare debugging and animation tools, and cover security testing, test-driven development, Bluetooth integration tests, WebRTC, and VoIP apps. Across the talks, the speakers explain practical tradeoffs and tools teams can use to build and maintain React Native applications.