Reducing FOOMs in the Facebook iOS app

This post details Meta's efforts to reduce out-of-memory (OOM) crashes in the Facebook iOS app. It describes the process of identifying OOMs through logging and process-of-elimination, profiling memory usage to pinpoint issues with UIWebView, migrating to WKWebView to offload memory usage to a separate process, optimizing allocation rates, and implementing an in-app memory profiler using Objective-C method swizzling to track object allocations and detect leaks. The post highlights the importance of addressing OOMs as a blind spot in traditional crash reporting and the impact of these efforts on app reliability.