Contrary to what people are saying here. You should try to validate the idea with your target market and maybe even go so far as getting payment before building the product.

You can test if you really have an understanding of the problem you're solving and if it's even worth building in the first place. I've personally gone down so many dead ends following my business ideas without validating first and I won't be caught dead making the same mistake.

Another benefit of talking with your customers is that you can collect information about how to market towards them. You listen to their problems and the solutions they're using and you instantly have ideas about blog posts you can write and other ways you can provide value for your target customer.