iOS 9 added a News app (think of it as Apple's version of Flipbook and Zite). A companion app for Mac OS X El Capitan would seem like a natural, but it's nowhere to be found.
In iOS 9, News compiles articles you've expressed interest in from several sites. Stories are pulled from a range of sources, from top news organizations to indie publications. Stories are chosen for you based on what you like to read. Apple says that the more you use News, the better it gets at picking out just what you’ll want to see.
You can share articles with others and save them to read later. Thanks to iCloud, stories are saved on all your iOS devices, so you can start reading something on your iPhone and pick it up later on your iPad. It would be nice to also be able to do this with a Mac.
You can set up News to provide a continuously updated feed of stories that are collected based on your likes and interests in a "For You" section. You can also add specific publications to a "Favorites" section.
It's not a perfect app — don't expect it to truly collect all new articles on a topic such as "running" — but it's useful and easy to use. There are Zite and Flipboard versions for the Mac as well as iOS, so I'm not sure why Apple hasn't offered a News version for El Capitan.
Of course, for that matter, when are we going to get Siri on the Mac?