It's just a webpage to generate RSS feed as far as I know and not an app. I guess you could add it as a PWA.

I just grab the RSS feeds and add them to PodcastGuru since I think that's what nostr:npub1dergggklka99wwrs92yz8wdjs952h2ux2ha2ed598ngwu9w7a6fsh9xzpc's plan for the site is.