Apple is having a rough week. First it had to pull its iOS 8 update due to reports of broken Touch IDs and paralyzed cell service. Now it's defending allegations that the iPhone 6 and 6 Plus can bend in a user's pocket—Apple says it's received just nine customer complaints of bent iPhones in the first six days of phone sales. Apple also outlined the gauntlet of durability testing it says it puts its phones through—five tests in particular:

Three-point bending: Apple's tests place pressure on iPhones in varying degrees to...