Coding an application with Twitter API use to be a lot of mess prior to iOS 5. There was no inbuilt support from Apple side. For even basic message tweeting, you had to integrate third party libraries like SAOAuth and MGTwitterEngine.
Apple has realized Twitter is very important functionality for any App to proliferate in Social arena. Twitter being Simple and open source project is perfect choice for Apple to integrate in iOS 5.
With Twitter APi integration you can let your friends know when you scored highest in the game, when you clicked that nice photograph or when you have a website URL for reference.
Twitter is now very integral part of iOS 5 Architecture. Lets see how to build a basic Twitter Client App for Apple iOS 5 API without any frills.