[agordhandas]

Assuming your users are also users of Slack, I highly recommend creating shared channels; that way, they can reach out to you in your slack, without leaving their own. Email is great, but there is something about IM that feels way better.

Also, if you are offering your product/service for free initially, I would say, "it's free, but in exchange you gotta give us 20 minutes on a call every week/every other week". This ends up being super valuable.

[moooo99]

Depending on the target demographic, Discord might also be a good Slack alternative. It seems like its the preferred platform for many projects nowadays