Unit Testing in Xcode, does it run the app?

The application is actually run but there is a trick you can use to prevent it from running.

int main(int argc, char* argv[]) {    int returnValue;    @autoreleasepool {        BOOL inTests = (NSClassFromString(@"SenTestCase") != nil                     || NSClassFromString(@"XCTest") != nil);            if (inTests) {            //use a special empty delegate when we are inside the tests            returnValue = UIApplicationMain(argc, argv, nil, @"TestsAppDelegate");        }        else {            //use the normal delegate             returnValue = UIApplicationMain(argc, argv, nil, @"AppDelegate");        }    }    return returnValue;}

Here's a variation of Sulthan's answer that uses XCTest, which is the default for test classes generated by XCode 5.

int main(int argc, char * argv[]){    @autoreleasepool {        BOOL runningTests = NSClassFromString(@"XCTestCase") != nil;        if(!runningTests)        {            return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));        }        else        {            return UIApplicationMain(argc, argv, nil, @"TestAppDelegate");        }    }}

This goes into main.m, which should be under Supporting Files in a standard project layout.

Then in your tests directory add:

TestAppDelegate.h

#import <Foundation/Foundation.h>@interface TestAppDelegate : NSObject<UIApplicationDelegate>@end

TestAppDelegate.m

#import "TestAppDelegate.h"@implementation TestAppDelegate@end

In Swift, I prefere to bypass a normal execution path inside application: didFinishLaunchingWithOptions:

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {    guard normalExecutionPath() else {        window = nil        return false    }    // regular setup    return true}private func normalExecutionPath() -> Bool {    return NSClassFromString("XCTestCase") == nil}

Code inside guard will remove any views created from storyboard.