Just should actually do community building from the first second on. The easiest way is to share your idea and getting feedback on it. We developed a product for this. It is called STOMT. For example the game "Empires of the Undergrowth" (not on the market yet) intensively uses STOMT to collect feedback in form of short wishes (you can label them as a page owner). We also have integrations for a lot of platforms so people don't have to leave your product: https://www.stomt.com/empires-of-the-undergrowth

Also works well for ourselves: https://www.stomt.com/stomt

You can think of STOMT as consumer-friendly GitHub Issues.