Wanted: RSS reader for Social Media-feeds - recommendations?

Again and again it is mentioned as an elementary advantage of Mastodon & Co. that ActivityPub-feeds are accessible from everywhere thanks to RSS. That's true - but I don't have the right reader for such a purpose. I would like to have a doomscrolling-timeline for all the services that are accessible via RSS, not an article-reader like RSS clients usually are - with previews, open article, etc.

Is there an app like 'Fritter' that not only allows access to Twitter, but also to follow accounts via Nitter, Mastodon, PeerTube, etc. etc.? Can be for Android or Windows...