The Facebook app includes a massive amount of functionality. Open up the hamburger menu and you’ll see a subset of what it does: feed, groups, profiles, video,

The Facebook app includes a massive amount of functionality. Open up the hamburger menu and you’ll see a subset of what it does: feed, groups, profiles, video, marketplace, events, camera app, search, crisis response, etc. Each of these has a very deep level of functionality. Facebook are also very data driven, which means they’re probably testing multiple versions of most features at any given time. Each of the products is implemented by their own team. I wouldn’t be surprised if there are literally thousands of engineers commuting changes to the iOS app on a regular basis. If you are on a small team you can make a lot of headway against bloat on your own. For an app like Facebook it would be incredibly difficult to understand the entire thing, let alone make much of a difference. Technologies like React Native are supposed to address bloat. It’s much more efficient to ship incremental features in JS (can even be done over the network), but React Native doesn’t solve every use case, and Facebook has a lot of legacy code.