When viewing a drawn schematic from an email would get out of hand, if viewed by switching apps, needing to print but don't have printer, or on iPad Air 2 and iPad Pro that will only allow "Slide Over" to work. The "Split View" feature would allow you to switch your right screen from email to safari and vice versa for searches and keep the left side running iCircuit.

For more info

https://developer.apple.com/library/prerelease/ios/documentation/WindowsViews/Conceptual/AdoptingMultitaskingOniPad/index.html