OTP verification are very much essential for 2 Factor authentication which adds extra layer of security. So we are going to implement a basic application for the implementation of OTP validation in Xamarin forms application.

If you want to go through whole setup process then watch this tutorial : https://youtu.be/gA2KugrGIog

So first thing first :
Step 1 : Sign Up with Twilio
https://www.twilio.com/
Notes :
1. You have to enable Twilio Trail Number
2. You have to copy the AccountSID and AUTH Token and paste it inside your project.

Step2 : If you want to understand more about Twilio Dashboard and configuration watch my video : https://youtu.be/gA2KugrGIog

Step 3 : Application side :
MainPage.Xaml

MainPage.xaml.cs

At last working project download it from here : http://xamaringuyshow.com/otpvalidationxamformstut68/

Additional Note : If you are sending test message to some one abroad.

1.Add countries where you want to give access to.
2. Verify the user phone number [Only on the trail account]