I hear this over and over again but don't understand why "complex" suddenly means "non-idiomatic UX." Most iOS apps follow common design patterns, and IB makes building these patterns extremely straightforward. For the one-off odd screens, sure, don't use IB, but certainly if you are building an iOS app the majority of screens will not require crazy unique UX. If they do that is probably a design smell.
Really? Every app I see in the top ten and every app clients want me to build for them is customized out the wazoo, with nary a stock control in sight. Most apps these days have highly dynamic content too, with elements resizing, moving around, and appearing and disappearing based on context. IB is worse than useless for this kind of UI and editing AutoLayout in IB should be considered cruel & unusual punishment.
