How to force users to subscribe without creating an account?

Question

I've created a web app which does not require a user to create an account, you just fill in a form and get the result.

I thought that would be nice to add "Enter your email" input text along with the CTA of my landing page (a "Try now for free" button), in order to force the users to subscribe my mailing list in exchange of using my web app.

My concern is that with that approach every time a user refreshes the page would have to enter their email again to use the app.

I came up with the following fixes:

1. Store their email in a cookie so the input text gets automatically filled in.
2. Asking for their email at the end of the app form.
3. Sending a unique URL with the results page to their email (this would increase the interaction cost, but all emails would be verified).
4. Don't make it mandatory, just add some CTA in the landing or result pages.

What option do you think is best? Do you have a better alternative?

Answer 1

1. I think I would find it odd if a random website would display an email I typed in an input field a while back. Maybe it would be better to just hide it.

2. Valid option.

3. I doubt people would use the "new" link. I, as a user, would just use the old link as long as it works.

4. Valid option. If it is not too distracting, I don't think users would mind.

Answer 2

I think you'll find that the best strategy to 'persuade' (rather than 'force') users to subscribe is to provide very clear and transparent information about the value of doing this (versus not doing this) rather than anything you can do through the user interface or interaction design.

This is because the users have to make a trade-off between providing you with their details (which may cost them nothing in terms of a transaction value, but has a cost associated with it later down the track when this information is used to generate value for the people who possess it), and the value that they will gain through the benefit of the subscription (which might not be completely clear to them in terms of current and future value).

If you can clearly show that the benefit outweighs the cost for the user, you won't have to do anything else.

Answer 3

I think if you require an email, you should use a form of option one so that the user only needs to enter it once.

Instead of storing their email in a cookie, you could use a session cookie. Session cookies are signed by the server, which means that the user can't modify it. The session cookie would just confirm that the user has subscribed, it wouldn't store the email.

When the user enters their email, you'd create the session cookie to confirm that it has been done. When the session cookie exists, you'd either hide the email text box or show a message like ":check: you've already subscribed to our mailing list".

I agree that you should, however, make this an option that your persuade rather than force. I think option 2 is likely to be the best for this