What are some alternatives?
When comparing FetchRSS and RSS.app, you can also consider the following products
PolitePol - Online tool for creation of RSS feeds for any web page
Full Text RSS Feed Builder - FullTextRSSFeed.com converts abbreviated RSS feeds to a full text version, for free.
FiveFilters Feed Creator - Create feed from elements (e.g. links) extracted from a given web page
Feedity - Create RSS feed for any webpage or podcast. Extract data and turn dynamic websites into spreadsheet or API. Feedity is an online RSS feed generator and podcast feed builder tool. Display feeds on website.
Update Scanner - Update Scanner is a Firefox extension to monitor web pages for updates.
Keep Me On Top - Create RSS feeds from Hacker News, Reddit, Lobsters, newsletters, etc. Or get a periodic email summary.