What happens when your business has a portfolio of products/services over multiple departments, spanning various platforms, and only one consumer mobile app uses Unity for an augmented reality component that's not a core offering (premium feature)?
But to answer your question, they are royalties on top of that one mobile app, not your entire revenue. If you distribute it for free, you might pay no royalties; if it somehow is tightly related to your main revenue-generating product then you’d sign a custom licensing agreement with them.
I love mattermost and use it on the daily.
I got it as a self hosted version of discord but I played around with the focalboard as well.
Being a project manager I felt it held its own against many of other SaaS overpriced project boards like Monday.com.
still needs some work though but I'd recommend it.
As far as chat mattermost does look like a very good Slack-alternative near-F/OSS alternative, but these days Matrix and Zulip are also very good. Did you happen to try those options/do a bakeoff?
As far as kanban/task management goes, Gitea/GitLab/GitHub feels like the right place these days (for software companies). Are there any reasons you prefer a standalone tool over putting the PM stuff a bit closer to the code?