Using a single button for sign-in and sign-up

Question

What's the best label to put on the OAuth button (google/facebook) which allows both registration and signing in?

We really see little sense of having two separate buttons which does exactly same thing - authenticate the user. However we had a (vary) few customers mailing us to ask how to register as they only see sign-in button. How to label this button so it is more clear and inline with google's branding policies?

Answer 1

"Continue with..." seems to be the best and most comprehensive label for when the use-case includes both Signing in and Signing up.

Saying that, you should also consider guidelines for each of those platforms.

Consider that users rely on consistent experience across different use-cases: they will look for the button that looks and feels familiar, so the less change you make, the better it generally is. Guidelines are a good help for that:

• Google says you should use "Sign in with Google" with their button (or "Sign up with Google" when the use-cases are separated);
• Facebook says you should use "Continue with Facebook" on their button for both use-cases;
• Apple says you should use "Continue with Apple" if it's united and "Sign in with Apple"/"Sign-up with Apple" if they're separated.

Answer 2

"Continue with Google"

"Continue with Facebook"

If the user already has the account, he/she will be logged in. If not, The user will have a new account and logged in