You can just create a category and create a custom method to add any view you want - images,buttons,sliders.
Foe example, here is the code that i use - it adds custom backgroundimage,backButton and Label.
@interface UINavigationBar (NavigationBar)
-(void)setBarForCard;
@end
@implementation UINavigationBar (NavigationBar)
-(void)setBarForCard
{
UIImageView *aTabBarBackground = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"BarImage"]];
aTabBarBackground.frame = CGRectMake(0,0,self.frame.size.width,44);
[self addSubview:aTabBarBackground];
[self sendSubviewToBack:aTabBarBackground];
[aTabBarBackground release];
UIButton *backBtn = [UIButton buttonWithType:UIButtonTypeCustom];
backBtn.frame =CGRectMake(10, 8, 60, 30);
[backBtn addTarget:self action:@selector(back:)forControlEvents:UIControlEventTouchUpInside];
[backBtn setImage:[UIImage imageNamed: @"Back"] forState:UIControlStateNormal];
[self addSubview:backBtn];
UILabel *calendar = [[UILabel alloc]init];
calendar.frame = CGRectMake(105, 13, 109, 21);
calendar.text = @"Calendar"
calendar.textColor = [UIColor whiteColor];
calendar.textAlignment = UITextAlignmentCenter;
calendar.shadowColor = [UIColor grayColor];
calendar.shadowOffset = CGSizeMake(0, -1);
calendar.font = [UIFont fontWithName:@"HelveticaNeue-Bold" size:20];
calendar.backgroundColor = [UIColor clearColor];
[self addSubview:calendar];
}
And then, in any view controller, you can change your navigationbar by calling [self.navigationController.navigationBar setBarForCard];
This works both in IOS 4 and IOS 5
