The source files are exclusively Sketch, and Photoshop/PSD is absent. The UI design community has been shifting for more than a year, Apple started releasing UI templates in Sketch in addition to Photoshop in 2015 — Google even earlier.<p>Illustrator is still highly relevant for its strength, vector based work, while Sketch has surpassed Photoshop for UI.<p>The momentum is only increasing, even with bugs and issues found in Sketch. It's obvious the interface design community desires better tools. I wonder if Adobe Comet stands a chance with disruption we're seeing?