Swiggy Manjunath Chandrashekar Apr 25, 2023

How We Improved Our Android App Cold Start Time by 53%

Article Summary

Swiggy's Android team cut cold start time by 53% in three months. Here's the playbook that drove a 2.2% conversion lift.

The Swiggy mobile team systematically tackled Android app launch performance using Firebase Performance SDK and Systrace. Their methodical approach to identifying and fixing bottlenecks resulted in measurable business impact and immediate user feedback.

Key Takeaways

Critical Insight

A systematic approach to Android cold start optimization delivered 53% faster launches and drove measurable conversion improvements.

The team's tooling strategy (Systrace + Firebase + Android Studio) revealed surprising bottlenecks that most teams overlook.

About This Article

Problem

Swiggy's Android app was slow to start because the main thread had too much work to do. The app was using reflection unnecessarily and doing file I/O operations during startup, which meant users had to wait before they could interact with the UI.

Solution

The team fixed this by removing the main thread blockers, loading branding images asynchronously, and skipping JSON deserialization at startup. They also simplified the launch screen by replacing nested layouts with a flat view hierarchy.

Impact

Users immediately noticed the app felt faster and more responsive. Firebase Performance data confirmed the improvements were consistent across the user base after the update went live.