Native module RNCWebView tried to override RNCWebViewModule. Check the getPackages() method in mainapplication.java

Comment out the following line in MainApplication.java and try.

@Override
protected List<ReactPackage> getPackages() {
	@SuppressWarnings("UnnecessaryLocalVariable")
        List<ReactPackage> packages = new PackageList(this).getPackages();
        //packages.add(new RNCWebViewPackage());
}