Limiting registration to be only by Facebook, is it a good idea?

Question

I'm building a web application which is available as a stand-alone website as well as a Facebook App, the target audience are mostly Facebook users.

However, I'm confused about the registration process: I want to promote my app! I want to publish updates from my web app to users' Facebook timelines (in a non-spammy manner) so that my app is auto-promoted among their connections, and therefore I need people to register in my application's facebook app and grant it permissions to post on their behalf. To ensure this, I tend to allow registration only by Facebook. i.e, no email registration, a registration is only possible if you click the "Login with Facebook" button and register through the Facebook App.

On the other hand, I myself hate logging with Facebook, whenever possible, I choose to register with my email address and not Facebook. And sometimes even I just don't register if there's no way to do that other than "with Facebook", is that only me or people tend to be like that?

If people hate "Login with Facebook" will that affect my app's UX? and will that drawback my app's promotion rather than help promoting it?

I need to hear your opinions. Existing examples (websites) are recommened.

Answer 1

Requiring facebook is a bad idea. There is a significant number of people that don't use FB and there's no reason to exclude them. And others, even if they do use FB, prefer to register through other avenues (twitter, google+ etc.). Best to be as flexible and accommodating as possible, for both the immediate concern of acquiring registrations and the larger concern of your brand image.

Answer 2

Sounds like you need to research your audience and their reactions to Login with Facebook a bit more. Spotify received a great deal of negative feedback when they started forcing FB login as their only system.

If you can identify lost opportunities as a result of imposing FB logins on users then you should provide an alternative, unless you're happy to let them go. Perhaps you could allow them to sign up with an alternative service / a simple email address and make a bigger deal of highlighting the benefits to the user of linking their FB profile. If they still choose to use other details then you could extend the Facebook call to action with options to Like the page / app through profile and/or email notifications.

Answer 3

Fairly sure this is a duplicate question, but here's some research:

http://blog.mailchimp.com/social-login-buttons-arent-worth-it/

Mailchimp, an application with hundreds of thousands of users tried to get people to sign up with social media buttons, and after a while noticed that it was having absolutely no impact on their sign ups.

Instead of investing the time and money (and time is more valuable) in integrating Facebook into your log in experience, A/B test your front page, and see what happens. If people like your app, they'll share it, and the value of a word-of-mouth share, rather than a forced post-to-wall, is much greater.

On the other hand, some apps do lend themselves to greater integration with Facebook. Like mentioned in another answer, Spotify got an initial backlash, bit they've really pivoted their experience to be a social one, which I think has pettishly impacted their app. Now, if only they would pay musicians a fair share. If this is your app, you an still test the sign up experience.

You might find that people sign up with an email address, but then link to Facebook from within the app.