Easily Mock Up iOS 7 Apps & Interfaces with a Free iOS 7 GUI Template PSD
The designers at Teehan+Lax have built a complete iOS 7 GUI elements template, and are now offering it for free as a very functional PSD file. Everything is fully layered, well-labeled, and organized logically, making it an excellent tool to use for mocking up apps and concepts as they would appear natively in the completely redesigned iOS 7 interface.
Being a PSD it is obviously aimed at Photoshop, but it works perfectly fine in Pixelmator in our testing, and all layers remain intact (at least in Pixelmator 2.2).
Do note that because iOS 7 is currently in beta, some of the elements may change slightly from the beta release to the final release. We can expect Teehan+Lax to update the template file for any significant changes though. Happy designing.