When presenting a new view with a UIBarButtonSystemItemCompose button in the navigation bar, the position is slightly off and adjusts after the view has come into view.
Nice observation, This problem solved in viewDidAppear. Can you please check this..
- (void)viewDidAppear:(BOOL)animated{
[super viewDidAppear:animated];
UIBarButtonItem* composeBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCompose target:nil action:nil];
[self.navigationItem setRightBarButtonItem:composeBarButtonItem animated:YES];
}
This might help you :)