Up to this point, we've been running our application strictly on simulated hardware. It is important that we take it one step further and run on actual mobile devices to be sure the application performs in the way that we expect. In this section, we'll discuss running React Native applications on both iOS and Android devices.
Before submitting your app to the App Store, it's highly recommended that you first test your app on physical hardware. In fact, the more devices you can test on, the better. Simulators are great for rapid development testing, but they don't give you an honest sense of how the app feels in your hands. Are the touch targets large enough? Are the animations smooth on lower end hardware? Does the app feel responsive? These are all questions that are best answered with actual device testing.
Not long ago, Apple required that developers pay $99/year to join the Apple Developer Program in order test iOS apps on hardware...