Feature flags allow development teams to separate code deployment from feature release. It has grown to be an essential tool for testing in production, A/B testing, and controlled rollout. Controlled rollout using feature flags is a way to deliver features to your users safely, but doing it on mobile comes with some challenges. How do you propagate feature flagging configuration to mobile devices that don’t always have a strong network? As a mobile developer, you want to be able to use the latest flag configuration, but you also don’t want to stop someone using the app just because you can’t load the feature flag config. In this talk, we'll start with why controlled rollout is important and how feature flags enable you to do it successfully, then we will talk about mobile specifics, and then a demo with React Native.