+(void)showPopup:(NSString *)title
         message:(NSString *)message
     buttonTitle:(NSString *)buttonTitle
   popupDelegate:(id)popupDelegate
 
{
	/**
	 * Recreates UIAlertView functionality using 1 line of code:
	 * example:
	 *  #import "Static.h"
	 *  [Static showPopup:@"Error!"
	 *			message:@"You need an internet connection to view this page."
	 *		buttonTitle:@"OK"
	 *	  popupDelegate:nil];
	 */
	UIAlertView *openURLAlert = [[UIAlertView alloc] initWithTitle:title
                        message:[NSString stringWithFormat:message]
                        delegate:popupDelegate
                        cancelButtonTitle:buttonTitle
                        otherButtonTitles:nil];
    [openURLAlert show];
    [openURLAlert release];
}

Checking for NULL

NSString *myString = [[NSString alloc] init];
if ([myString length] > 0) {}  //check the string's length instead of checking for NULL or nil
 

Auto-Detect Languages (and iPhone current Language)

NSArray *languages = [[NSArray alloc] initWithArray:[NSLocale preferredLanguages]];
for (id language in languages) {
	NSLog(@"Language: %@", language);
}
NSLog(@"Default Language: %@", [languages objectAtIndex:0]);

Auto-Detect Country

NSLocale *locale = [NSLocale currentLocale];
NSString *code = [locale objectForKey:NSLocaleCountryCode];
NSString *countryName = [locale displayNameForKey:NSLocaleCountryCode value:code];
NSLog(@"country name: %@", countryName);

Changing your files' "Path Type" is also imperative in synchronizing files between multiple developers/computers. To get to the Path Type, right-click (ctrl+click) your file(s) and hit 'Get Info'.
Under the General tab of the pop-up you'll see your Path Type. xCode defaults files to being "Relative to Enclosing Group".

If you're going to organize your files into folders in Finder and then add them into xCode without checking "Copy items into designation group's folder (if needed)", it's imperative to change the Path Type to "Relative to Project". You'll notice the Path under your files' Name will change.

Example: Adding a Default.png image to the application. The image exists in my "Application's folder/images" folder.
Name: Default.png
Path: images/Default.png

This changes the application's start up image so that it doesn't need to be in the same folder as your .xcodeproj file.