There are many issues where iOS 8 changes things. AutoLayout constraints and orientation handling to name two. A third issue is the ubiquitous view animation to move a textField away from the keyboard, that respects the issues in landscape or portrait. Here's my production-grade implementation.
Check these cool apps out from Digital Hermosa:
LeadCapture - the professional method for making contact recording at trade shows fun .
KnittingQueen - productivity tools for knitters of all skills & ages.
DR_M - the drummer's metronome with cool strobe effects.
Say It On Billboard - animated signs of graphics and text for limo drivers.