Check for iPhone 3.5",4",4.7" or 5.5"

if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone) {
        CGSize result = [[UIScreen mainScreen] bounds].size;
        
        if(result.height == 480)
        {
            NSLog(@"Device is iPhone 4");
        }
        if(result.height == 568)
        {
            NSLog(@"Device is iPhone 5s");
        }
        if (result.height == 667) {
            NSLog(@"Device is iPhone 6");
        }
        if (result.height == 736) {
            NSLog(@"Device is iPhone 6 Plus");
        }
    }