Try and talk with your potential customers.<p>* Build a landing page where you explain what you want to build<p>* Add a pricing page and ask for money<p>* Ask for users address if interested<p>* If enough interest is shown - build your first MVP<p>Here's a more detailed example about validating an idea - <a href="https://blog.bufferapp.com/idea-to-paying-customers-in-7-weeks-how-we-did-it" rel="nofollow">https://blog.bufferapp.com/idea-to-paying-customers-in-7-wee...</a>