updated 12:42 pm EDT, Tue May 13, 2014
iPads will be limited to two simultaneous apps
According to sources said to be familiar with the feature's development, iOS 8 should include a new split-screen multitasking option on the iPad. A long-running complaint about iOS has been its inability to run multiple apps simultaneously (with certain exceptions, such as audio apps). While some form of visible multi-tasking is common elsewhere in the phone and tablet industry, more recent non-Apple phones and tablets have been able to run two or more apps undue compromise, thanks to multi-core processors; Samsung's Galaxy Tab Pro 12.2 can run up to four apps at once.
Apple is reportedly planning to limit split-screen usage to two apps in landscape mode. Users may, however, be able to drag content from one app to another -- and Apple is also said to be developing new ways for apps to interact with each other. This could include sharing content, something still blocked in iOS 7.
Split-screen has reportedly been designed with 9.7-inch iPads in mind, and so it's unclear if Apple will allow the feature on the iPad mini. The option may be a highlight of Apple's rumored 12.9-inch iPad. It could also premiere at next month's WWDC, but Apple sometimes keeps iOS features secret until new supporting hardware is ready to be announced.