Consulted to a small electronics manufacturer for software support to an existing in-development ridesharing system consisting of a vehicle, in-vehicle interface module, custom smartphone app, and cloud-based backend support systems. The project scope involved deep integration between embedded hardware components and consumer-facing software solutions, requiring swift troubleshooting and enhancement cycles across multiple platforms. Throughout the engagement, successfully added enhancements and fixes to both the in-vehicle interface module and the custom smartphone app. Improvements included refinement of real-time communication protocols, expansion of diagnostic logging capabilities, and iterative user interface updates driven by field feedback. These upgrades directly contributed to increased system stability and user experience consistency across diverse operating environments. In parallel, assisted in performing tests of the full ridesharing system, working collaboratively with development and field engineers to validate cross-system functionality. Testing sessions included real-world trials, stress testing under simulated passenger loads, and edge-case scenario verification to ensure the robustness of cloud-sync features and module-to-app synchronization logic.