Update 5 April '18 :

react-native-firebase-phone-auth-corrected

This npm includes a correction over react-native-firebase-phone-auth npm from given link https://www.npmjs.com/package/react-native-firebase-phone-auth :-

Problem in Android : -

1. In “react-native-firebase-phone-auth” library firebase object has not created in “RNFirebasePhoneAuthModule.java”. They are already implemented the firebase object logic but code is commented out.
2. method does not override or implement a method from a supertype @override.

Resolution for Android : -

1. Uncomment FirebaseOptions Builder object from “RNFirebasePhoneAuthModule.java” and Comment FirebaseApp.initializeApp() method without firebase object parameter.
2. Removed override method “createJSModules()” From "RNFirebasePhoneAuthPackage.java”. Resolution suggested by the owner of “react-native-firebase-phone-auth” library from given url https://github.com/ashinga48/React-Native-Firebase-Phone-Authentication/issues/3 .

Getting started

$ npm install react-native-firebase-phone-auth-corrected --save

Mostly automatic installation

$ react-native link react-native-firebase-phone-auth-corrected

Manual installation

iOS

1. In XCode, in the project navigator, right click Libraries ➜ Add Files to [your project's name]
2. Go to node_modules ➜ react-native-firebase-phone-auth-corrected and add RNFirebasePhoneAuth.xcodeproj
3. In XCode, in the project navigator, select your project. Add libRNFirebasePhoneAuth.a to your project's Build Phases ➜ Link Binary With Libraries
4. Run your project (Cmd+R)<

Android

1. Open up android/app/src/main/java/[...]/MainApplication.java

...
•	Add import com.reactlibrary.RNFirebasePhoneAuthPackage; // <--- imports at the top of the file
•	Add new RNFirebasePhoneAuthPackage() <--- to the list returned by the getPackages() method

2. Append the following lines to android/settings.gradle :

...
include ':react-native-firebase-phone-auth-corrected'
project(':react-native-firebase-phone-auth-corrected').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-firebase-phone-auth-corrected/android')

3. Insert the following lines inside the dependencies block in android/app/build.gradle :

...
compile project(':react-native-firebase-phone-auth-corrected')

Usage

1. Import DeviceEventEmitter in react-native

2. Import RNFirebasePhoneAuth from 'react-native-firebase-phone-auth-corrected'

   import {
       //...
       DeviceEventEmitter,
   } from 'react-native';
   
   import RNFirebasePhoneAuth from 'react-native-firebase-phone-auth-corrected';

3. (Optional) initialize Firebase

       /*
           All info appId, projectId, appKey, databaseURL
           can be found in google-services.json file which you can download
           from firebase console in the website
       */
       RNFirebasePhoneauth.initFirebase(
           appId,
           projectId,
           appKey,
           databaseURL,
           (resp)=>{ console.log(resp) },
           (error)=>{
               //alert(error); console.log(error);
               },
       );

4. Add event listener for OTPStatus in componentDidMount

       componentDidMount() {
            this.initFirebase(); // if needed
            this.listenToOTP();
        }
   
        listenToOTP(){
   
            DeviceEventEmitter.addListener('OTPStatus', (data) => {
   
                switch(data.CODE){
                   case "SENT":
                           //SMS Sent
                       break;
                   case "VERIFIED":
                            //SMS Received & read by google play services
                             let authData = {
                                 code : data.OTPNumber,
                                 verificationId : data.verificationId
                             }
                             firebase.auth().signInWithPhoneAuth(
                                authData,
                                (success)=>{
                                    //on Successful Login
                                },
                                (error)=>{
                                    //on Error
                                });
                        break;
                   case "ERROR":
                           //error sending SMS
                       break;
                }
   
                if(data.CODE == "ERROR")
                    {
                    }
   
            });
   
   
        }

5. Lastly Send OTP to a phoneNumber

       let phoneNumber = "+61412341234";
       RNFirebasePhoneauth.sendOTP(phoneNumber);

   That's it!!!

// TODO: Android & iOS Firebase link RNFirebasePhoneAuth;

Common Issues on Build / Integration

1 : Failed to resolve: com.google.firebase:firebase-core:X.X.X

follow this link, it worked for me
https://stackoverflow.com/questions/37310188/failed-to-resolve-com-google-firebasefirebase-core9-0-0

2 : Did you setup Firebase for Android & iOS properly??

https://support.google.com/firebase/answer/7000104?hl=en

OR

- ANDROID issue #1 - Add firebase configuration file to the root of the project in android
    https://support.google.com/firebase/answer/7015592

- ANDROID issue #2 - build.gradle config did run perfectly with this configuration

    ```
    compileSdkVersion 25
        buildToolsVersion "25.0.2"

        defaultConfig {
            applicationId "com.ivu"
            minSdkVersion 16
            targetSdkVersion 26


2. iOS