If you're an iOS app designer you've probably been using some sort of template over the years which aids your design direction. It helps you figure out the spacing required, the default iOS design, whether you should use the design style and much more.
iOS 7 is a huge change so app designers will definitely need to update their designs to fit in with the new OS. Teehan+Lax, a company very well known for its very well put together iOS templates has kindly updated its PSD kits to add iOS 7. The kit is based on BETA 1 of iOS 7 so things may change when it comes to final release but they have promised to update the PSD if things do.
The iOS 7 PSD kit includes everything you'll need to help you design and fit your apps into the new OS. Everything is very nearly organised into folders and it includes various sample screens to help you get an idea of Apple's design direction.