- Reach out to people 1-on-1 who fit your customer profile. I did a research sprint and got lots of people to test out my MVP after following up with responses to my polls about SXSW. You can read more about the research sprint technique I used here: What I Learned About Your SXSW Experience (and it's totally worth the extra time to do it this way!). Similarly, @kevinrose started a Facebook group and added everyone there for his new meditation app. He provides constant updates and gets continuous engagement through there. Lots of people offered to help with designing the app!
- /r/startups has a great weekly feedback and support thread. My reccomendation would be to start somewhere small like a forum or an industry Slack channel to get your first points of feedback. Improve / polish based on things you hear. Take a week or two to improve, don't dilly dally. Then take things up a notch by sharing somewhere like BetaList. You can (and should!) think about doing a launch here on PH too. P.S. not the advertising reddit linked here (clicked the wrong product!) go for the real real :)