In iOS 5, Mobile Safari , which--until now--let you save article URLs for later reading; those saved URLS were synced between devices, so you could access your list of saved links on any iOS device running iOS 5 or any Mac running Lion (OS X 10.7) or later. But Reading List under iOS 5 was essentially a glorified folder of bookmarks: Opening a saved URL still required a live Internet connection to actually load the article.

In iOS 6, Reading List is much more useful. Now, whenever you add an article to your Reading List, the entire article--text, images, layout, you name it--is saved to your device and synced to your other iCloud-enabled devices and computers. In other words, assuming each of those devices and computers have at some point connected to the Internet to sync the latest Reading List changes, you'll be able to access and read your saved articles, even if you're offline.

To add the currently viewed article to your Reading List in iOS, you just tap the Share button in Safari and then tap Add To Reading List. If you want to add a link on the current page, without having to visit the link first, just tap and hold the link until a menu appears, and then tap Add To Reading List in that menu.

On the iPad, you get a third option: When viewing the Reading List, you can add the frontmost webpage by tapping the plus-sign (+) button at the top of the list. (On your Mac, you just choose Bookmarks -> Add To Reading List, or press Shift+Command+D.)

To access your Reading List on an iPhone or iPod touch, you tab the Bookmarks button in Safari and then tap Reading List. (If you're already in a sub-list in the Bookmarks list, tap the left-facing arrow until you get to the top level, titled Bookmarks.) On an iPad, you tap the Bookmarks button and then tap the Reading List (glasses) icon at the bottom of the Bookmarks popover. You can access a similar list on your Mac by clicking the Reading List (glasses) icon in Safari's toolbar.