XYPieChart is an simple and easy-to-use pie chart for iOS app. It started from a Potion Project which needs an animated pie graph without interaction. All animation was implemented in the drawRect: method. After played with BTSPieChart, really like its code structure, it’s clean, has well named functions, structure like a UITableView. XYPieChart rewrote the code, based on CALayers for the animation. Compared to BTSPieChart, XYPieChart is a prettier version, it has a simpler insert/delete slices algorithm, different design of slice selection, more flexible to customize.