I recently talked to nearly 100 entrepreneurs for my book titled "How We Did It". One thing that I asked most of them was how to validate the business idea before embarking on it. One common answer was to set up a landing page and advertise it using the right keywords on Adwords. Are people proceeding towards the purchase/download from here? In that case, there is a market and you could work on your idea.

Incidentally, the chapter about idea validation is available for free here: https://www.dropbox.com/s/0evrb66hvg4ucoy/Preview-copy.pdf

This is the Amazon link for the book : http://www.amazon.com/How-Did-entrepreneurs-struggles-experi...