1. Explain popular apps of iPhone?

Face book-Social networking
Doodle Buddy-drawing
Pandora Radio-radio on our iPhone
Yelp-restaurant reviews

2. Explain iphone architecture?

It is similar to MacOS X architecture

It acts as an intermediary between the iPhone and iPod hardware an the appearing applications on the screen

The user created applications never interact directly with the appropriate drivers, which protects the user applications from changes to the hardware.

3. Please explain the difference between shallow copy and deep copy?

Shallow copy is also known as address copy. In this process you only copy address not actual data while in deep copy you copy data.
Suppose there are two objects A and B. A is pointing to a different array while B is pointing to different array. Now what I will do is following to do shallow copy.
Char *A = {'a','b','c'};
Char *B = {'x','y','z'};
B = A;
Now B is pointing is at same location where A pointer is pointing.Both A and B in this case sharing same data. if change is made both will get altered value of data.Advantage is that coping process is very fast and is independent of size of array.
while in deep copy data is also copied. This process is slow but Both A and B have their own copies and changes made to any copy, other will copy will not be affected.

4. Explain the requirements for developing iPhone Apps?

Mac OS 10.5/10.6 iPhone SDK (Software Development Kit 3.0/4.0).
IPhone SDK consists of:

IDE to develop iPhone Apps is XCode(This tool is inbuilt in iPhone SDK)
Interface Builder This is used to design GUI of Apps(Inbuilt feature of iPhone SDK)
Instruments This is used to check any memory leaks in our apps (Inbuilt in SDK)
Simulator This is used to test our apps before deploying into real device.

5. Define about the applications that can be used with iphone?

Technology, Entertainment and Design(TED):
Allows to watch and listen to world's most fascinating people have to say, all on the iPhone.

Market Watch:
Breaking news about the investments can be seen. To do so, open the Stocks app and rotate.

Latest runway shows, videos from Vogue's fashion library, reviews, exclusive party pictures, fashion news updates can be seen on Style.com.

6. Where can you test Apple iPhone apps if you do not have the device?

iOS Simulator can be used to test mobile applications. Xcode tool that comes along with iOS SDK includes Xcode IDE as well as the iOS Simulator. Xcode also includes all required tools and frameworks for building iOS apps. However, it is strongly recommended to test the app on the real device before publishing it.

7. Explain which JSON framework is supported by iOS?

SBJson framework is supported by iOS. It is a JSON parser and generator for Objective-C. SBJson provides flexible APIs and additional control that makes JSON handling easier.

8. Explain does iOS support multitasking?

iOS 4 and above supports multi-tasking and allows apps to remain in the background until they are launched again or until they are terminated.

9. Explain fast enumeration?

Fast enumeration is a language feature that allows you to enumerate over the contents of a collection. (Your code will also run faster because the internal implementation reduces
message send overhead and increases pipelining potential.)

10. Explain why iPhone apps are popular?

Give our business a whole new way of transacting business for millions of users.
IPhones are the market leaders in the smart phone segment. The iPhone has become a great device to surf the internet, play games, interact with social networks and transact business.

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