Question: I am trying to write ReactJs app and I found a useful React-Native library. Will I be able to use it in my code?

Answer: 
Nopes, its not recommended, since react-native library may have `<View>` and other components which are react-native specific and can blow up in react js
You can not use react native library in react project because they both have different dependencies while as react compiles with the help of webpack but in react native there are OS-level dependencies while making the build and the main difference is that React Native totally depends on native models of OS and does not use any HTML like React or other web-development frameworks.

refer this [doc](https://www.cognitiveclouds.com/insights/what-is-the-difference-between-react-js-and-react-native/) for more detail