As promised during Apple's September event, updates for iOS and OS X El Capitan have been made available for Pages, Numbers, and Keynote, including the much-hyped split-screen function, with some extra support for the new 3D Touch feature.
Even though the updates were anticipated after the announcement and release of iOS 9, they're still a little late to the scene -- a month late, to be a little more accurate. While the reason for the delay is unknown, the assistive upgrades are certainly welcome.
As mentioned above, split-screen for Pages caters to Apple users who are multitaskers at heart, with Slide Over, Split View, and Picture at-the-ready for iPad. The productivity features, which have been touted by the company as of late, are most likely related to their competitor Microsoft -- as The Verge noted, their split-screen feature has been available for their Office programs long before Apple began to design them for their own devices.