By Todd Bernhard
As Donald Rumsfeld used to say, there are known unknowns and unknown unknowns. The iPhone 7 and iPhone 7 Plus have been introduced, which means it's time to speculate on the the known unknown for the next iPhone. That phone could be the iPhone 6 SE or the iPhone 7s or the iPhone 8. Regardless of what it's called, the features the next iPhone ought to have could be compelling.