Optimising Page Load Times in Flipkart Mobile App

Flipkart shaved 30% off page load times in their React Native app with 500M weekly visits. Here's how they did it without rewriting everything.

With 180M+ downloads and users on flaky networks with low-end devices, Flipkart's engineering team spent a year optimizing their hybrid React Native architecture. They focused on React Native bridge bottlenecks and network layer improvements.

Key Takeaways

• Sending data as strings vs nested objects cut bridge writes 3x, improving loads 15-20%
• Batching bridge calls beat multiple small calls, even with identical data transfer
• Predictive prefetching gave 10% more users instant page loads
• Parallelizing fragment creation with API calls saved another 5-10%
• Architecture shift: moved from native-first to React store-first rendering

The team discovered that lock synchronization costs more than string deserialization, a counterintuitive finding that changed their entire data transfer strategy.