Great use of negative space to incorporate 2 subjects into one: an airplane and a map icon symbol to represent traveling. It's easily understandable what this app icon is for, and the scaleability would work well since it's such a simply design.
Buy App Icon Creator with Flat Shadow Generator by wearesometimes on GraphicRiver. The iOS 7 App Icon Creator, automates the process of creating 10 various icons sizes. You just need to edit the large.