In a recent usability post of Raluca Budiu, the common mobile app pattern of sliding menus is criticized: when the menu button is at the left edge and the content slides away to the right, then hiding the menu again requires the user to move her hand, and reading the menu items requires her to move her finger out of the way. With fat fingers, this is even more of a problem.
So UISplitViewController is the new default for iOS apps. Most iPhones have compact-sized size classes. iPads have regular sized ones. The iPhone 6(s) Plus mixes both. Only horizontally regular-sized environments show both the master and the detail scene (or primary and secondary view controller).
A UISplitViewController has a master and a detail view controller. When the selected item is deleted and the detail is visible, you can perform a segue. If the detail is not visible, performing a segue to change the detail will present it. I didn’t want that. There are two cases where you will want to change the detail although it’s not visible: