Reducing the Size of Cash App for iOS
Article Summary
Cash App cut their iOS app size in half in one year. Here's the playbook they used to get from 245 MB to 126 MB downloads.
John Szumski from Cash App shares how their team systematically reduced both download and install sizes while maintaining four separate binaries (app, widget, and two Siri extensions). They used Emerge Tools and Bazel to identify and eliminate bloat across their modular codebase.
Key Takeaways
- Dependency pruning saved 60 MB download by removing duplicate code across 4 binaries
- Resource optimization with ImageOptim and runtime generation cut 11 MB downloads
- Compiler flags and indirect enums reduced code size by 18 MB
- Pre-merge Starlark tests catch dependency mistakes before CI runs
- Install size dropped from 608 MB to 303 MB on iPhone 13
Critical Insight
Cash App reduced iOS download size by 49% (245 MB to 126 MB) through systematic dependency pruning, resource optimization, and automated size checks.
