If marketing is a primary focus - a classic technique is to comment on relevant threads in your category - filtered RSS feeds from Quora, StackOverflow, Google Alerts, HN, Reddit, etc.

It only takes a second to review a thread and see if you can add value with a comment (and possibly plug your service).

Could use Zapier's Digest app to get them all at the end of a day/week so you don't have noisy alerts all day. Slack and/or email is usually a solid way to get those alerts.