I happily use formspark.io for both Lunar (https://lunar.fyi/contact https://lunar.fyi/contact), The Low-tech Guys (https://lowtechguys.com/contact https://lowt

I happily use formspark.io for both Lunar (https://lunar.fyi/contact https://lunar.fyi/contact), The Low-tech Guys (https://lowtechguys.com/contact https://lowtechguys.com/contact) and my personal website (https://alinpanaitiu.com/contact https://alinpanaitiu.com/contact). A contact form that's customizable with simple HTML inputs, gets redirected to your email, and you can just reply to that email to begin a discussion with that user. I've had great success with it, users know how to use it, they're happy when they get a prompt response and they like the privacy (as opposed to having to create a public post on forums/Github/Discord). You also get free bot protection with botpoison or the usual captcha. There are some false positives as usual, which is why I also have a Discord server running for the apps. But Formspark goes 99% of the way and it's incredibly cheap with a free option. EDIT: I see you're mostly looking for a way to reach your users instead of letting the users reach you. I feel that's not something most users want. I almost never like when I get an unsolicited email after I start using an app, and unsubscribe instantly. It's better to provide good documentation (maybe a simple organized markdown page to start with), and one as clear as possible first page. People will reach you when they need more info and you can update the website and documentation based on the feedback to minimize the repetitive interactions.