I have the following questions about iPhone application development. 1. Does it make any distinction from the perspective of an iPhone network application whether the iPhone is using 3G or Wi-Fi for network support? If yes, then what are the differences from application development perspective? 2. What happens when my application running on the iPhone is interfered by an incoming phone call? My running application terminates or runs in the background allowing the reception of the phone call or anything else? 3. How to add "Previous" and "Next" keys on iPhone's default keyboard and their functionalities? 4. How to dynamically reduce the View size to make place for the keyboard appearance and prevent elements at lower portion of the View from being hidden beneath the appeared keyboard? 5. Which approach is better for building a View: 1. Use a nib file 2. Create the view dynamically in initWithFrame: and why? Is it possible for a View that is initialized by a nib file to reduce its size? 6. How to determine that a UITextField has become the firstResponder (currently selected) just now? 7. If I use a navigation controller and push a view in it, the back button is automatically added to top left corner with the title of the previous View. How can I make the title "back" instead of the "Previous View title"? Thanks in advance.