QACR: A Comprehensive Mobile Crash Reporting and Monitoring System at Qunar

Jiang Baogui, a senior engineer at Qunar, introduces the QACR (Qunar Application Crash Reporter) system, which he has helped design and maintain for over two years to support more than 20 Qunar mobile apps, handling up to 80,000 logs daily.

1. Full‑coverage SDK collection – QACR gathers a wide range of exception types, including Android Java crashes, ANR, native library crashes, iOS crashes, React‑Native crashes, memory leaks, and custom business exceptions. It also captures comprehensive runtime context such as stack traces, logcat output, device model, app version, network status, memory usage, screenshots, and custom tags, enabling fast root‑cause analysis.

2. Deep backend parsing – The backend synchronizes with the latest MPortal data interface to retrieve git repository information, performs symbolication and de‑obfuscation using mapping or dSYM files, extracts business‑line keywords, and automatically creates BugIDs. It then routes bugs to the appropriate developers via QMQ, QTalk, and email.

3. Real‑time monitoring – After parsing, metrics are recorded in the watcher service, which automatically creates alerts if thresholds are exceeded. Alerts are sent to business‑line owners and callbacks trigger QACR to keep the monitoring 24/7.

4. Assignment and auto‑assignment – Bugs can be manually assigned, or automatically assigned by matching the faulty class, line number, and version to the last submitter. If the submitter is still employed, they receive a QTalk and email notification; otherwise, the business‑line admin is prompted to assign a developer.

5. Rich reporting – QACR generates daily, new‑version, and monthly reports that summarize crash counts, affected user numbers, trend charts, top‑10 problematic bugs, and distribution of crash devices and OS versions, helping TLs, RDs, and QA track app quality over time.

6. Conclusion – The system now supports more than 20 Qunar apps, processes massive log volumes, and aims to serve additional products and teams, facilitating rapid, agile development and delivering a smoother user experience.