Nearly every other IDE has this already!

It doesn't make sense that IB is a separate application.

This could be done by automatically providing stub methods, or by enhancing Code Sense so that it knows about unimplemented adopted protocol methods. Or some other even smarter way.

String parameters are everywhere and I don't like having to type @" all the time. Xcode should just add a placeholder when I'm calling a method that takes an NSString.

Whenever I disconnect my iPhone, Xcode should default to the simulator instead of complaining.

Add a dialogue that would search for files in project in a fuzzy fashion as TextMate does

When you get build errors the Build Results window pops up. I would prefer to have the list of errors docked to my main editor window. Or at least, even if it was a separate window, double-clicking an error should navigate the main editor to the corresponding line of code.

Instead of:

NSString *myString;
@property (nonatomic, retain) NSString *myString;
@synthesize myString;

..this should be enough:

@property NSString *myString;

Add this to the end of a .h file:

- (void)test
@end

Go to the implemenation file. Compile. The compiler will now complain about a missing semicolon in the .m file!!? Weird.

Currently Xcode has plug-ins but no public API for them. Let's have one and extend Xcode/IB with new languages.

Xcode needs better file navigation. The user should be able to quickly jump to a class, ideally by hitting a shortcut and typing the class name. The user should also be able to easily bring up a list of recently opened files, sorted by most recent.

If you drag a view on to a second monitor to work on it, save, disconnect the second monitor and then try to display the view again, it will open off screen. There is no way to get it back on to the screen without reconnecting the second monitor, or opening the xib file in a text editor and changing some coordinates.

Snapshots are too heavyweight. Look at IntelliJ for how local history should work.

When I type a method signature in my header file, please just stub it out for me in the implementation file (and vice versa)

Since Objective-C method names come in many parts it can be difficult to read. Take this method for example:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath

It would help if one could set a different font size and color for the actual name of the method, in this case tableView:cellForRowAtIndexPath:.

Display them in mouse over tool tips and menus. Make it easy to assign shortcuts.