Android SMS Verification App - Phone Verification with OTP

Hello friends, I got a lots of emails and facebook requests to post a tutorial for phone number verification. Some people also asked me for SMS verification code for android. So in this tutorial we will create an Android SMS Verification App.

You already seen this example in some popular applications like WhatsApp, Hike etc. They verify the user’s phone number by sending an OTP (One Time Password) to the phone number registered.

To avoid spamming this is the best way to confirm your user with their phone number. And that is why verifying user’s with their phone number is one of the most common feature for your android app now days.

So in this tutorial we will create an Android SMS Verification App for registered users.

Android SMS Verification App – Video

You can check this video to know what we will be creating in this Android SMS Verification tutorial.

Creating our SMS API

To verify the user’s phone number we will send the verification code via SMS. For sending SMS we need an SMS API.
SMS’s are of two types
- Promotional: It will not be sent to DND activated phone numbers. So for OTP or Phone verification we cannot use promotional sms.
- Transactional: It will be sent to all numbers, doesn’t matter a number has activated DND or not. In this tutorial I am using Transactional sms.
The bad news is for you guys is I haven’t found any provider who is providing SMS API for free. This tutorial is sponsored by Cheap SMS Bazaar. They gave me some free transactional sms credits to write this tutorial.
There are a lot of SMS API provider’s you can google for them. You can also buy it from Cheap SMS Bazaar. If you will signup to Cheap SMS Bazaar, they would give you 10 free promotional sms. You can test this tutorial with promotional sms as well. But with promotional sms your sms will not be sent to DND activated numbers.
I am assuming that you all are using Cheap SMS Bazaar. So go to your dashboard. And then go to API Documents. I am using the transactional one and my API link is.

http://login.cheapsmsbazaar.com/vendorsms/pushsms.aspx?user=abc&password=xyz&msisdn=919898xxxxxx&sid=SenderId&msg=test%20message&fl=0&gwid=2

user: Your login username.
password: Your login password.
msisdn: Single mobile number or multiple mobile numbers separated by comma(10 digits or +91).
sid: Approved sender id(Only 6 characters).
msg: Your message content(Minimum 459 characters/3 messages).
fl: if flash message then 1 or else 0
gwid: 2 (its for Transactions route.)
Note: Only 100 mobile numbers are allowed.

We will send the sms to only a single mobile number.
We will get the following JSON in response.

{

"ErrorCode":"000",

"ErrorMessage":"Success",

"JobId":"381a8090-b230-42fa-ac04-157cc2142bfa",

"MessageData":[

{

"MobileNumber":"919898xxxxxx ",

"MessageParts":[

{

"MessageId":"919898xxxxxx -67e3765cdf034f438a432eacb88d0c14",

"MessagePartId":1,

"MessageText":"test message"

}

]

}

]

}

Creating Database and Scripts for Android SMS Verification Application

Go to phpMyAdmin and create the following table. (I am using Hostinger’s free hosting).

As you can see I have 6 columns. ID is PRIMARY KEY and AUTOINCREMENT Username and Phone is set to UNIQUE. verified is TINY INT and will store only two values 0 and 1. (o means not verified and 1 means verified). The default value for verified is set to 0 i.e. for every row the default value is unverified. And when user will enter the correct verification code we will change it to 1 i.e. verified.
Go to your server’s directory and create a folder for this project. (I created AndroidOTP)
We need to connect to the database first, so create a script dbConnect.php and write the following code.

<?php

define('HOST','mysql.hostinger.in');

define('USER','u502452270_andro');

define('PASS','belal_123');

define('DB','u502452270_andro');

//Connecting to database

$con = mysqli_connect(HOST,USER,PASS,DB) or die('Unable to Connect');

Now to handle the registration request create a file register.php. This file would store the user detail to database. It will also send the OTP or Verification Code via SMS.

<?php

//Constants for our API

//this is applicable only when you are using Cheap SMS Bazaar

define('SMSUSER','your user name');

define('PASSWORD','your password');

define('SENDERID','your sender id');

//This function will send the otp

function sendOtp($otp, $phone){

//This is the sms text that will be sent via sms

$sms_content = "Welcome to Simplified Coding: Your verification code is $otp";

//Encoding the text in url format

$sms_text = urlencode($sms_content);

//This is the Actual API URL concatnated with required values

$api_url = 'http://login.cheapsmsbazaar.com/vendorsms/pushsms.aspx?user='.SMSUSER.'&password='.PASSWORD.'&msisdn=91'.$phone.'&sid='.SENDERID.'&msg='.$sms_text.'&fl=0&gwid=2';

//Envoking the API url and getting the response

$response = file_get_contents( $api_url);

//Returning the response

return $response;

}

//If a post request comes to this script

if($_SERVER['REQUEST_METHOD']=='POST'){

//getting username password and phone number

$username = $_POST['username'];

$password = $_POST['password'];

$phone = $_POST['phone'];

//Generating a 6 Digits OTP or verification code

$otp = rand(100000, 999999);

//Importing the db connection script

require_once('dbConnect.php');

//Creating an SQL Query

$sql = "INSERT INTO androidotp (username, password, phone, otp) values ('$username','$password','$phone','$otp')";

//If the query executed on the db successfully

if(mysqli_query($con,$sql)){

//printing the response given by sendOtp function by passing the otp and phone number

echo sendOtp($otp,$phone);

}else{

//printing the failure message in json

echo '{"ErrorMessage":"Failure"}';

}

//Closing the database connection

mysqli_close($con);

}

After sending the OTP to user’s mobile number we need to confirm the OTP from user. And for this we need one more php file. Create a new file confirm.php and write the following code.

<?php

//If a post request is detected

if($_SERVER['REQUEST_METHOD']=='POST'){

//Getting the username and otp

$username = $_POST['username'];

$otp = $_POST['otp'];

//Importing the dbConnect script

require_once('dbConnect.php');

//Creating an SQL to fetch the otp from the table

$sql = "SELECT otp FROM androidotp WHERE username = '$username'";

//Getting the result array from database

$result = mysqli_fetch_array(mysqli_query($con,$sql));

//Getting the otp from the array

$realotp = $result['otp'];

//If the otp given is equal to otp fetched from database

if($otp == $realotp){

//Creating an sql query to update the column verified to 1 for the specified user

$sql = "UPDATE androidotp SET verified = '1' WHERE username ='$username'";

//If the table is updated

if(mysqli_query($con,$sql)){

//displaying success

echo 'success';

}else{

//displaying failure

echo 'failure';

}

}else{

//displaying failure if otp given is not equal to the otp fetched from database

echo 'failure';

}

//Closing the database

mysqli_close($con);

}

Thats it for the server side part. Note the URL for the both the files register.php and confirm.php. And lets create an Android Project.

Android SMS Verification Project

Open Android Studio and create a new project and add the following dependencies that will be used.

dependencies {

compile fileTree(dir: 'libs', include: ['*.jar'])

testCompile 'junit:junit:4.12'

compile 'com.android.support:appcompat-v7:23.1.0'

compile 'com.android.support:design:23.0.0'

compile 'com.mcxiaoke.volley:library-aar:1.0.0'

}

I have added volley because in this android sms verification tutorial I am using volley for the network operations. And for the layout design I have added design:23.0.0.
Now in your project create a java class to store the important constants that will be used in our app. I created Config.java

package net.simplifiedcoding.androidotp;

/**

* Created by Belal on 11/18/2015.

public class Config {

//URLs to register.php and confirm.php file

public static final String REGISTER_URL = "http://simplifiedcoding.16mb.com/AndroidOTP/register.php";

public static final String CONFIRM_URL = "http://simplifiedcoding.16mb.com/AndroidOTP/confirm.php";

//Keys to send username, password, phone and otp

public static final String KEY_USERNAME = "username";

public static final String KEY_PASSWORD = "password";

public static final String KEY_PHONE = "phone";

public static final String KEY_OTP = "otp";

//JSON Tag from response from server

public static final String TAG_RESPONSE= "ErrorMessage";

}

Now we need to design a registration activity. I have created the following layout for this android sms verification.

android sms verification — Android SMS Verification

For creating the above layout you can use the following code.

<?xml version="1.0" encoding="utf-8"?>

<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"

android:background="@color/colorBackground"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:fitsSystemWindows="true">

<LinearLayout

android:layout_gravity="center_vertical"

android:orientation="vertical"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:paddingLeft="24dp"

android:paddingRight="24dp">

<ImageView

android:background="@drawable/logo"

android:layout_gravity="center_horizontal"

android:layout_width="150dp"

android:layout_height="150dp" />

<android.support.design.widget.TextInputLayout

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_marginTop="8dp"

android:layout_marginBottom="8dp">

<EditText android:id="@+id/editTextUsername"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:inputType="textEmailAddress"

android:hint="username" />

</android.support.design.widget.TextInputLayout>

<android.support.design.widget.TextInputLayout

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_marginTop="8dp"

android:layout_marginBottom="8dp">

<EditText android:id="@+id/editTextPassword"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:inputType="textPassword"

android:hint="Password"/>

</android.support.design.widget.TextInputLayout>

<android.support.design.widget.TextInputLayout

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_marginTop="8dp"

android:layout_marginBottom="8dp">

<EditText android:id="@+id/editTextPhone"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:inputType="textEmailAddress"

android:hint="Phone" />

</android.support.design.widget.TextInputLayout>

<android.support.v7.widget.AppCompatButton

android:id="@+id/buttonRegister"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:background="@color/colorPrimary"

android:textColor="@color/colorAccent"

android:layout_marginTop="24dp"

android:layout_marginBottom="24dp"

android:padding="12dp"

android:text="Register"/>

<TextView android:id="@+id/linkSignup"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:layout_marginBottom="24dp"

android:text="Already have an account? Login here"

android:gravity="center"

android:textSize="16dip"/>

</LinearLayout>

</ScrollView>

After user will tap the REGISTER button, a dialog box will appear to enter the confirmation code sent. For this dialog box we need to create a layout resource file. Create dialog_confirm.xml file and write the following code.

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:padding="@dimen/activity_horizontal_margin"

android:layout_margin="@dimen/activity_horizontal_margin"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:background="@color/colorPrimaryDark"

android:orientation="vertical">

<TextView

android:textColor="@color/colorAccent"

android:text="Enter the code received"

android:layout_width="wrap_content"

android:layout_height="wrap_content" />

<EditText

android:id="@+id/editTextOtp"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:inputType="textEmailAddress" />

<android.support.v7.widget.AppCompatButton

android:id="@+id/buttonConfirm"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:layout_marginBottom="24dp"

android:layout_marginTop="24dp"

android:background="@color/colorPrimary"

android:padding="12dp"

android:text="Confirm"

android:textColor="@color/colorAccent" />

</LinearLayout>

Now come to MainActivity.java.

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package net.simplifiedcoding.androidotp;

import android.app.AlertDialog;

import android.app.ProgressDialog;

import android.content.Intent;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.support.v7.widget.AppCompatButton;

import android.view.LayoutInflater;

import android.view.View;

import android.widget.EditText;

import android.widget.Toast;

import com.android.volley.AuthFailureError;

import com.android.volley.NetworkResponse;

import com.android.volley.Request;

import com.android.volley.RequestQueue;

import com.android.volley.Response;

import com.android.volley.VolleyError;

import com.android.volley.toolbox.JsonObjectRequest;

import com.android.volley.toolbox.StringRequest;

import com.android.volley.toolbox.Volley;

import org.json.JSONException;

import org.json.JSONObject;

import java.util.HashMap;

import java.util.Map;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

//Creating views

private EditText editTextUsername;

private EditText editTextPassword;

private EditText editTextPhone;

private EditText editTextConfirmOtp;

private AppCompatButton buttonRegister;

private AppCompatButton buttonConfirm;

//Volley RequestQueue

private RequestQueue requestQueue;

//String variables to hold username password and phone

private String username;

private String password;

private String phone;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

//Initializing Views

editTextUsername = (EditText) findViewById(R.id.editTextUsername);

editTextPassword = (EditText) findViewById(R.id.editTextPassword);

editTextPhone = (EditText) findViewById(R.id.editTextPhone);

buttonRegister = (AppCompatButton) findViewById(R.id.buttonRegister);

//Initializing the RequestQueue

requestQueue = Volley.newRequestQueue(this);

//Adding a listener to button

buttonRegister.setOnClickListener(this);

}

//This method would confirm the otp

private void confirmOtp() throws JSONException {

//Creating a LayoutInflater object for the dialog box

LayoutInflater li = LayoutInflater.from(this);

//Creating a view to get the dialog box

View confirmDialog = li.inflate(R.layout.dialog_confirm, null);

//Initizliaing confirm button fo dialog box and edittext of dialog box

buttonConfirm = (AppCompatButton) confirmDialog.findViewById(R.id.buttonConfirm);

editTextConfirmOtp = (EditText) confirmDialog.findViewById(R.id.editTextOtp);

//Creating an alertdialog builder

AlertDialog.Builder alert = new AlertDialog.Builder(this);

//Adding our dialog box to the view of alert dialog

alert.setView(confirmDialog);

//Creating an alert dialog

final AlertDialog alertDialog = alert.create();

//Displaying the alert dialog

alertDialog.show();

//On the click of the confirm button from alert dialog

buttonConfirm.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

//Hiding the alert dialog

alertDialog.dismiss();

//Displaying a progressbar

final ProgressDialog loading = ProgressDialog.show(MainActivity.this, "Authenticating", "Please wait while we check the entered code", false,false);

//Getting the user entered otp from edittext

final String otp = editTextConfirmOtp.getText().toString().trim();

//Creating an string request

StringRequest stringRequest = new StringRequest(Request.Method.POST, Config.CONFIRM_URL,

new Response.Listener<String>() {

@Override

public void onResponse(String response) {

//if the server response is success

if(response.equalsIgnoreCase("success")){

//dismissing the progressbar

loading.dismiss();

//Starting a new activity

startActivity(new Intent(MainActivity.this, Success.class));

}else{

//Displaying a toast if the otp entered is wrong

Toast.makeText(MainActivity.this,"Wrong OTP Please Try Again",Toast.LENGTH_LONG).show();

try {

//Asking user to enter otp again

confirmOtp();

} catch (JSONException e) {

e.printStackTrace();

}

new Response.ErrorListener() {

@Override

public void onErrorResponse(VolleyError error) {

alertDialog.dismiss();

Toast.makeText(MainActivity.this, error.getMessage(), Toast.LENGTH_LONG).show();

}

}){

@Override

protected Map<String, String> getParams() throws AuthFailureError {

Map<String,String> params = new HashMap<String, String>();

//Adding the parameters otp and username

params.put(Config.KEY_OTP, otp);

params.put(Config.KEY_USERNAME, username);

return params;

}

};

//Adding the request to the queue

requestQueue.add(stringRequest);

}

});

}

//this method will register the user

private void register() {

//Displaying a progress dialog

final ProgressDialog loading = ProgressDialog.show(this, "Registering", "Please wait...", false, false);

//Getting user data

username = editTextUsername.getText().toString().trim();

password = editTextPassword.getText().toString().trim();

phone = editTextPhone.getText().toString().trim();

//Again creating the string request

StringRequest stringRequest = new StringRequest(Request.Method.POST, Config.REGISTER_URL,

new Response.Listener<String>() {

@Override

public void onResponse(String response) {

loading.dismiss();

try {

//Creating the json object from the response

JSONObject jsonResponse = new JSONObject(response);

//If it is success

if(jsonResponse.getString(Config.TAG_RESPONSE).equalsIgnoreCase("Success")){

//Asking user to confirm otp

confirmOtp();

}else{

//If not successful user may already have registered

Toast.makeText(MainActivity.this, "Username or Phone number already registered", Toast.LENGTH_LONG).show();

}

} catch (JSONException e) {

e.printStackTrace();

}

new Response.ErrorListener() {

@Override

public void onErrorResponse(VolleyError error) {

loading.dismiss();

Toast.makeText(MainActivity.this, error.getMessage(),Toast.LENGTH_LONG).show();

}

}) {

@Override

protected Map<String, String> getParams() throws AuthFailureError {

Map<String, String> params = new HashMap<>();

//Adding the parameters to the request

params.put(Config.KEY_USERNAME, username);

params.put(Config.KEY_PASSWORD, password);

params.put(Config.KEY_PHONE, phone);

return params;

}

};

//Adding request the the queue

requestQueue.add(stringRequest);

}

@Override

public void onClick(View v) {

//Calling register method on register button click

}

On success we are starting a new activity that is not yet created. So create a new activity named success. And write the following xml code for the layout file.

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:paddingBottom="@dimen/activity_vertical_margin"

android:paddingLeft="@dimen/activity_horizontal_margin"

android:paddingRight="@dimen/activity_horizontal_margin"

android:paddingTop="@dimen/activity_vertical_margin"

android:background="@color/colorBackground"

tools:context="net.simplifiedcoding.androidotp.Success">

<LinearLayout

android:layout_gravity="center_vertical"

android:orientation="vertical"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_centerVertical="true"

android:layout_alignParentStart="true">

<ImageView

android:background="@drawable/logo"

android:layout_gravity="center_horizontal"

android:layout_width="150dp"

android:layout_height="150dp" />

<TextView

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:layout_marginBottom="24dp"

android:text="You have successfully verified your phone number"

android:gravity="center"

android:textSize="16dip"/>

</LinearLayout>

</RelativeLayout>

The above code will produce the following layout.

For the java file of this activity (Success.java) I haven’t done anything.

package net.simplifiedcoding.androidotp;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

public class Success extends AppCompatActivity {

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_success);

}

At last add internet permission to your manifest file.

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

package="net.simplifiedcoding.androidotp">

<uses-permission android:name="android.permission.INTERNET" />

<application

android:allowBackup="true"

android:icon="@mipmap/ic_launcher"

android:label="Register"

android:supportsRtl="true"

android:theme="@style/AppTheme">

<intent-filter>

</intent-filter>

</activity>

</application>

</manifest>

Now run your application.

Bingo! Its working absolutely fine. You can get the project from GitHub Repository. Just go to the link given below.

Get Source Code of this Android SMS Verification App from GitHub

[sociallocker id=1372] Android SMS Verification Application[/sociallocker]

Some More Android Application Development Tutorial You Must Check

So thats all for this Android SMS Verification Tutorial. Please support by giving your feedbacks with your comments. And don’t hesitate to ask if having queries or confusions regarding this Android SMS Verification Tutorial. Thank You 🙂