I was able to import the demo feed successfully, but I’m not sure if it’ll work for every FreshRSS feed.

Use feeeed for iOS. Looks and feels more modern than a lot of the other RSS apps but without any stupid bs. Free with no ads. Has a built-in reader mode that strips out article ads. Developed by one very awesome dude.

It can handle more than just RSS content too- you can follow Bluesky/Mastodon accounts, YouTube channel uploads, subreddits, and more with it.

I highly recommend changing the default view from “cards” to “list” so you can see more content.