Lectures from the most recent quarter (Winter 2014-2015), based on iOS 8 and Swift are available on iTunesU.
The website you are looking at (http://cs193p.stanford.edu) was retired a couple of years ago, but evidently iTunesU folks still need it for demo code downloads, so we will post those below.
Downloads for previous quarters can be found to the left on this page.
Please do not repost from this website on other websites--these downloads are for the individual use of those of you watching the course on iTunesU. Enjoy!