About to launch my invoicing app, where to promote?

Ever since starting to freelance I wasn’t that happy with invoicing apps and always there was something missing for me. Also those absurd prices for features I didn’t feel needing made my just stick to web invoicing tools.

But those web invoices are also bot always the best and you also have to manually enter everything even for repeating customers etc.

So naturally as an iOS Dev I started building my own Invoicing Tool on the side and it‘s about to launch soon.

Of course as anyone being proud of his work I would like to get the word out into the world and show of what I got.

Now the question is where can I promote my app for free to reach my target audience of freelancers or small businesses owners that could need an offline, privacy first invoicing app.

I thought about posting in r/freelance or similar but couldn’t find a subreddit with my audience where I am allowed to promote.

Any ideas where I could find my audience of freelancers?