iphone xcode Landscape mode by default

Question

how can I set an iphone app to start in Landscape mode? and stays that way

Answer 1

Set the "Initial interface orientation" app.plist entry to "Landscape" (left or right home button) and add (or more likely, uncomment and edit) the following view controller method:

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
    // Return YES for supported orientations
    return UIInterfaceOrientationIsLandscape(interfaceOrientation);
}

Answer 2

Marcelo's answer is not correct, because UIInterfaceOrientationLandscape is not a valid identifier and thus brings up a build fail.

progrmr's answer is correct:

return interfaceOrientation == UIInterfaceOrientationLandscapeLeft || interfaceOrientation == UIInterfaceOrientationLandscapeRight;

(Apologies for not commenting on the first answer, but I didn't have enough reputation points when I wrote this...)