I have my responsive web application in place which works across all browsers. Now i am planning to work convert it into mobile application. Did some googling and can think of below ways to come up with mobile app
Approach 1 :- Can be done with the help of WebView (which actually will work as thin wrapper)
Approach 2 :-
Native App:- . Develop Native app. Now, If I need to develop the native , Can i use existing backend java code for Android/IOS/Windows platform or do i need to make modifications in that ? If yes will these modification vary per platform i.e. Android/IOS? For User interface, i believe i need to develop altogether separate views. Is that correct ? If yes will there be separate views for android and IOS ?
If your backend java code is sitting on a server behind some sort of API (REST etc.) then it can be used by both applications.
If you are developing natively for both platforms then you will need separate views. There are however solutions for developing for both platforms using a single codebase see: Xamarin Cordova