Monday, August 31, 2012 CSCI 333 – Systems Programming

Developing Apps for IOS

The Basics What is an app? App is simply short for application. It is computer software written for a specific user task. What is IOS? Originally iPhone Operating System, IOS is a mobile operating system developed and distributed by Apple. It was released in 2007 for the iPhone and the iPod Touch. It was later extended for the iPad and Apple TV.

The Basics What is Objective-C? It is a high-level, object-oriented programming language. It is the main language used for IOS and OS X application development. What is Cocoa Touch? It is the user interface (UI) framework for building IOS applications. It is based on Cocoa, which is the application programming interface (API) for the Mac operating system.

Developing Mobile Apps Mobile apps are designed for smart phones, tablets, and other mobile devices. How is developing mobile apps different than traditional software development? The screen size is limited to 320x480 pixels for iPhone and 1024x768 for iPad. Retina displays can double this resolution. Only one IOS application can be active and displayed on the screen at a given time. IOS applications have just one window to work with.

Developing Mobile Apps More differences between developing mobile apps and standard software IOS apps can read and write files in an area called a sandbox. There is limited access to the rest of the device. Programs need to open quickly and close down quickly. For example, If your app takes more than 5 seconds to give up control when the user hits the home button, the app may be killed. Conserving memory is important in writing apps. A device may have 256MB of RAM, but much of that is used for the screen and by other system processes.

Developing Mobile Apps IOS devices have features that many Macs do not have: Determining geographic coordinates Built-in camera Built-in accelerometer To develop apps for IOS, you will need: A Macintosh computer Xcode software To register as an Apple Developer