What services to use to create a test, the results of which can only be obtained by subscribing to the mailing list?

Question

Marketing

Which services to use to create a test, the results of which can only be obtained by subscribing to the mailing list.
You need something like Marquis, but to get the test result you need to subscribe to the mailing list in at least Viber and VK

Answer 1

Do it yourself

Answer 2

Write your layer in ten lines of code