At least as much as is needed for the job . Not every front end job needs React. js and even if it is needed not every needs the same level of knowledge. That being said: It is much more important to know how to design programs and how to program in general than to know the details of some JavaScript library.
Read moreWhich Indian companies use React Native?
We have picked here top 5 React Native development companies in India.
Read moreIs React Native worth learning in India?
Definitely . The experience in creating applications using native technologies can for example help in application distribution or working with mobile devices in general. However, creating both the user interface and business code in JavaScript may require a slight change of mindset.
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