I don't use the iHackerNews API for news:yc. It seemed too unreliable to use a third party service that seemed to keep having issues, and I didn't want user data to go through a third party. But I think it's cool to easily create a HN app without rewriting the scraping.
I scrape inside the app using a combination of libxml2, a custom XML wrapper for iOS, and then a horribly ugly (but pretty adaptable) chunk of objective-c to parse out the contents. This helps mostly for rate limiting issues: each device is rate limited as it should be.
