Sprite Kit is Apple's development framework with an Open-GL based renderer for 2-D and 2.5-D game developers. According to Apple Insider, the framework's "built-in support for physics makes animations look real, and particle systems create essential game effects such as fire, explosions, and smoke." Previously, iOS developers were able to use third-party platforms for the same purposes. Now that Apple has created its own tool, it is capable of staying with and growing with Apple, rather than being acquired and taken in a different direction. Rybakov said, "Ninety percent of the purchased applications are games, which are 2-D games in more than half of the cases, and Apple cares about its game developers."