Which is better authentication app or SMS?
Authenticator App (More Secure)
Using an authenticator app to generate your Two-Factor login codes is more secure than text message. The primary reason being, it's more difficult for a hacker to gain physical access to your phone and generate a code without you knowing about it.
Is SMS authentication free?
Yes, you read that right, you can set up a free two-factor authentication solution. How do you do it? By using OTP (One Time Password) technology in reverse. With this technique, you generate the code yourself in your application for your customer to send to a dedicated virtual number.