If the last section was about excellence in execution, this one is about conceptual excellence—the big idea.

This section features Wooden Labyrinth 3D, a life-like game, and Prowl, a notification utility. It'd be hard to find two apps that begin with such diametrically opposed use-cases. Wooden Labyrinth 3D is a time-sucking game that is hard to beat and even harder to put do wn. Prowl, by contrast, is a set-and-forget Growl utility meant to notify users of their computers' activity without taking up their time.

However, both demonstrate an acute awareness on the part of their developers of the way iPhone users interact with their devices. Wooden Labyrinth 3D is based on a classic game requiring the manual manipulation of two knobs to navigate through a wooden maze. Developer Elias Pietilä creates a 3D virtual maze and uses the iPhone's accelerometer-based inputs to make a game that's possibly even more interactive and addictive than the original.

On the other hand, when you see Zac West's Prowl app, you might be tempted to ask, "What's the big idea?" It's minimalist in spirit but incredibly useful for those who want to stay connected with their computer without being chained to it. It's an example of knowing what people want as much as knowing what they need: West built his push notifications with the capability to set quiet hours, customize profiles, and expand functionality. Know your user, these two projects suggest, and the big ideas will come.