Hi there HN - developer here! A bit of context:
Five months ago I launched this app, and so far I've had 850 installs and 55 in-app purchases.
The daily install rate bottomed out a few months ago at an average of ~2 installs per day, currently I'm around ~5 installs per day. I get a bunch of emails from users (I include a Feedback button in the app, and probably the most successful feedback forum was posting in r/Apple on their "Self-Promotion Saturdays" deal. ( https://old.reddit.com/r/apple/comments/by86cy/theres_an_app... )
I've pushed out over a dozen updates so far, but am transitioning into a slower release cadence, I wrote about that here ( https://spencerdailey.com/2019/10/18/about-currentkey-2-0-an... ) If anyone has any questions, shoot away! :D