Sometime when we need a specific way to interact with the phone or operator system which is various different between iOS and Android, that when we need to lean that responsibility to the OS it self.
In RN, most of the logic and UI, in the best way, must be consistent between platforms. So, In an advance level of bringing best user experience to end user, we need to create native module, that mean the leaning the logic to the Native Part. There are ton of article out there showing why and when we need to create a native module, I won't dive into explanation again. Instead, I will show you how can we create a native module that could be used in React native code. That mean, you write your Objective-C/Java code, and import and run it as a module in Javascript Code.
I will show you here the most basic way to create the most basic library, called: open https://google.com. It means, I want to open Google by using the default iOS/Android browser in a native way.