Planning or developing an App?
If you’re planning or developing an iPad or iPhone application then you need to check out the iOS Reference Library.
The Human Interface Guidelines clearly detail principles that will help you to design the best possible user experience for your iOS app. There are plenty of posts and articles providing different takes on what are perceived to be best practices but this is certainly the best place to start.
Once you’re up to speed we’d certainly suggest using one of the sets of stencils and toolkits that keep on popping up.
