I'm going to take a bit of different tact to other answers. TLDR: Don't look for "feedback", learn the customer/user and the problem they are trying to solve.

I'm going to take a bit of different tact to other answers. TLDR: Don't look for "feedback", learn the customer/user and the problem they are trying to solve. Communicating with users (or future users) is not really an issue I've faced with either of my startups (metaverse for outdoor sports https://ayvri.com https://ayvri.com & neurotech/sleeptech https://soundmind.co https://soundmind.co). I inherited Ayvri, but started SoundMind. The first thing is speaking to users, not something you do after. Who is your target user and where do you find them. I think if you are solving somebodies problem, or understand the problem you are solving it makes it easier to reach out and communicate with the users. It's difficult to reach out to existing users with a "can you give feedback" without really understanding the problem you are solving for them specifically, or asking about a problem. When working on Ayvri (then Doarama), we had a few paragliders who were really into the product. I'm not a paraglider (which always amazes that community) so I had no idea what they wanted. I looked at our most viewed 3D scenes, found out who made it, and reached out saying "hey, you're getting lots of views, and you clearly love the platform. I know nothing about paragliding and why you use our product, can you tell me about it, and how you use it and why?" Sure it's "feedback", but it's really about understanding what they are trying to accomplish and why they use the product. That is more important than getting "feedback" on what you've got. Understand the problem, and you may find solutions that the users don't know they need. With SoundMind, before we really didn't knew what the product would be, I was communicating with people on reddit re: neurotech, sleep, biohackers, etc. From there, I've had people (including investors) hunt me down on linkedin or message me on via reddit (HN has also been a good source). I dove deep into understanding people's problem with sleep, and from there we've focused on two initial HIGHLY specific use cases that we can help them with. So once we know who THOSE users are, again, it's fairly easy to speak to them.