What is 2-factor authentication?
It is a procedure introduced to ensure that only you can access your account – it is possible because you download an app which generates one-time passwords (OTP) on your mobile. Only after providing this code will you be able to access your account (meaning that nobody else will).
Which app should I download?
It is up to you since there are many apps of this kind. You can use Google Authenticator (for Android) or OTP Auth (for iOS).
Is it mandatory?
Yes. Due to the security of your funds and identity, there is no possibility to disable it.
How to set up 2FA?
Authentication app needs to be downloaded on your device, e.g. phone. Open your “Authenticator” application and add a new key. Choose the option “Scan barcode” and use your phone to scan the code displayed on a website. The app will give you a 6 digit code that you need to write down on a CoinDeal website. Remember that the code changes every 30 seconds.
Can I use Google Authenticator app without a smartphone?
Here is an explanation of how to set up a Google Authenticator on a different device: https://support.google.com/accounts/troubleshooter/4430955?hl=en#ts=4430956