The previously unreported addition to Apple's next-gen operating system was unearthed by Gear Live on Tuesday and adds to the already substantial list of new features that will roll out when Mountain Lion is released this summer.
New to Reading List in in the forthcoming OS X is the ability to read pages offline, a feature presumably facilitated by automatic on-site caching. Although it is not exactly known how Apple's system will work, it may be akin to available third-party software like the popular apps Instapaper and Readability, both of which offer offline reading on iOS devices.
Safari's Reading List, which debuted in 2011 in tandem with the no-frills Reader function, can be thought of as a smart bookmark button that offers users a way to quickly save and sort web pages for later reading. More than a bookmark, however, the Reading List keeps track of what a user has read and displays webpages ad-free.
Message displayed when attempting to access a webpage offline shows new Reading List mode. | Source: Gear Live
The system also leverages iCloud to automatically sync pages across all devices attached to an account, meaning that when a page is saved on a Mac, it is pushed to a user's iPhone, iPad or iPod touch. Safari's Reader tool can also be integrated with Reading List to consolidate text into a more digestible format for small screens.