if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
self.viewController = [[[_ViewController alloc] initWithNibName:@"_ViewController_iPhone" bundle:nil] autorelease];
} else {
self.viewController = [[[_ViewController alloc] initWithNibName:@"_ViewController_iPad" bundle:nil] autorelease];
}<pre name="code" class="objc">self.window.rootViewController = self.viewController;
[self.window makeKeyAndVisible];