Most begin with a cool idea. But Paul Graham of Y Combinator says: "Innovative ideas must address a market problem and unmet customer needs ... so ideas from elsewhere are almost always irrelevant for generating market value".
Do you know what market problem you are trying to solve?
Do you want to find out?
Propose what you think may be a market problem need and encourage friends, colleagues or potential customers to identify their needs so you may then devise an idea solution (perhaps close to your original idea) that will delight!