The iPhone offers standard view controllers for taking pictures with the camera and sending email from within your own application. The software ecosystem surrounding your application is extremely rich with such built-in services and applications. You should take advantage of these as much as possible. In this chapter, we’ll look at how you can do that.
Users look for application preferences in two main settings: in the application itself, and in the iPhone’s Settings application. For simple applications, applications with few preferences, and applications with preferences that need to be modified regularly, you should keep the preferences within the application itself. However, for more complicated applications, applications with complicated or numerous different preferences, and applications with preferences that the user will rarely have to modify, it’s preferable to use the Settings application.
Despite it being done in some applications currently for sale on the App Store, Apple advises that you should never split your preferences between the Settings application and a custom settings screen inside your own application. According to Apple, “If you have preferences, pick one solution and use it exclusively.” This is good advice; having multiple places to change settings is confusing not just for the user, but also for you as a developer.
Adding a preferences panel for your application to the main Settings application ...