I thought it was open source as soon as I saw the GitHub link. I imagine that’s why.
Since I don't have the funds to set up a server for hosting the website, GitHub Pages offers this service, and it's also a great platform for gathering user feedback.
The intention was to dupe people into thinking it's FOSS.
Very similar to DevUtils (https://devutils.com), but with a much more friendly pricing scheme which is great.
I'm curious though, why link to the GitHub site if it's not an open source app? You even do GitHub releases of what I guess are just the readme files and screenshots?