Using React Native Native Modules in Objective-C

I want to use a Native Module to get a data from React Native to Objective-C.I followed the demo from the documentation :

RCT_EXPORT_MODULE();RCT_EXPORT_METHOD(getEmail:(NSString *)email){  RCTLogInfo(@"Getting %@", email);}

I have my email into the RCTLogInfo but that's not what I want. And I'm a total newbie with Objective-C.

I would like to :

1. Save my email into a variable or something I could use and not just having it in a log...
2. I want to call it into AppDelegate to declare it to a module.

Example :[customFieldsDictionary setObject:email forKey:@"EMail"];

If someone sees this, it would saving my day!

Thank you!