The NSURLConnection class is actually pretty high level and does in fact handle things like caching, redirects, errors, etc. for you. I have been using ASIHttpR

The NSURLConnection class is actually pretty high level and does in fact handle things like caching, redirects, errors, etc. for you. I have been using ASIHttpRequest for a while -- it's not bad but can feel quite heavy at times. For future projects, I may roll my own HTTP lib by wrapping NSURLConnection directly. Btw, GCD and blocks in iOS 4 make it super easy to structure your network calls the same way you would in JavaScript with xmlhttprequest and closures, which makes async code much cleaner and easier to write.