Tutorial: Build an Android Robot Control App Using Kotlin and ROS 2

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A new developer tutorial demonstrates how to build an Android application in Kotlin that communicates with a ROS 2 robot over a WebSocket or MQTT bridge. The app uses Jetpack Compose for its control interface, allowing users to send movement commands via buttons or a virtual joystick mapped to velocity values. Robot telemetry such as battery level, odometry, and connection status is received by subscribing to designated ROS 2 topics and displayed using Kotlin coroutines and StateFlow. The architecture intentionally separates the UI layer from the ROS communication layer, making it easier to switch between simulators and physical robots. The guide also covers safety essentials including emergency stop functionality, command watchdogs, velocity limits, and TLS-secured authentication between the app and the robot.

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