Iphone – the default color for navigation bar buttons on the iPhone

It's certainly possible to develop on a Windows machine, in fact, my first application was exclusively developed on the old Dell Precision I had at the time :)

There are three routes;

1. Install OSx86 (aka iATKOS / Kalyway) on a second partition/disk and dual boot.
2. Run Mac OS X Server under VMWare (Mac OS X 10.7 (Lion) onwards, read the update below).
3. Use Delphi XE4 and the macincloud service. This is a commercial toolset, but the component and lib support is growing.

The first route requires modifying (or using a pre-modified) image of Leopard that can be installed on a regular PC. This is not as hard as you would think, although your success/effort ratio will depend upon how closely the hardware in your PC matches that in Mac hardware - e.g. if you're running a Core 2 Duo on an Intel Motherboard, with an NVidia graphics card you are laughing. If you're running an AMD machine or something without SSE3 it gets a little more involved.

If you purchase (or already own) a version of Leopard then this is a gray area since the Leopard EULA states you may only run it on an "Apple Labeled" machine. As many point out if you stick an Apple sticker on your PC you're probably covered.

The second option is more costly. The EULA for the workstation version of Leopard prevents it from being run under emulation and as a result, there's no support in VMWare for this. Leopard server, however, CAN be run under emulation and can be used for desktop purposes. Leopard server and VMWare are expensive, however.

If you're interested in option 1) I would suggest starting at Insanelymac and reading the OSx86 sections.

I do think you should consider whether the time you will invest is going to be worth the money you will save though. It was for me because I enjoy tinkering with this type of stuff and I started during the early iPhone betas, months before their App Store became available.

Alternatively, you could pick up a low-spec Mac Mini from eBay. You don't need much horsepower to run the SDK and you can always sell it on later if you decide to stop development or buy a better Mac.

Update: You cannot create a Mac OS X Client virtual machine for OS X 10.6 and earlier. Apple does not allow these Client OSes to be virtualized. With Mac OS X 10.7 (Lion) onwards, Apple has changed its licensing agreement in regards to virtualization. Source: VMWare KnowledgeBase

Modern approach

The modern way, for the entire navigation controller… do this once, when your navigation controller's root view is loaded.

[self.navigationController.navigationBar setTitleTextAttributes:
   @{NSForegroundColorAttributeName:[UIColor yellowColor]}];

However, this doesn't seem have an effect in subsequent views.

Classic approach

The old way, per view controller (these constants are for iOS 6, but if want to do it per view controller on iOS 7 appearance you'll want the same approach but with different constants):

You need to use a UILabel as the titleView of the navigationItem.

The label should:

• Have a clear background color (label.backgroundColor = [UIColor clearColor]).
• Use bold 20pt system font (label.font = [UIFont boldSystemFontOfSize: 20.0f]).
• Have a shadow of black with 50% alpha (label.shadowColor = [UIColor colorWithWhite:0.0 alpha:0.5]).
• You'll want to set the text alignment to centered as well (label.textAlignment = NSTextAlignmentCenter (UITextAlignmentCenter for older SDKs).

Set the label text color to be whatever custom color you'd like. You do want a color that doesn't cause the text to blend into shadow, which would be difficult to read.

I worked this out through trial and error, but the values I came up with are ultimately too simple for them not to be what Apple picked. :)

If you want to verify this, drop this code into initWithNibName:bundle: in PageThreeViewController.m of Apple's NavBar sample. This will replace the text with a yellow label. This should be indistinguishable from the original produced by Apple's code, except for the color.

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self)
    {
        // this will appear as the title in the navigation bar
        UILabel *label = [[[UILabel alloc] initWithFrame:CGRectZero] autorelease];
        label.backgroundColor = [UIColor clearColor];
        label.font = [UIFont boldSystemFontOfSize:20.0];
        label.shadowColor = [UIColor colorWithWhite:0.0 alpha:0.5];
        label.textAlignment = NSTextAlignmentCenter;
                           // ^-Use UITextAlignmentCenter for older SDKs.
        label.textColor = [UIColor yellowColor]; // change this color
        self.navigationItem.titleView = label;
        label.text = NSLocalizedString(@"PageThreeTitle", @"");
        [label sizeToFit];
    }

    return self;
}

Edit: Also, read Erik B's answer below. My code shows the effect, but his code offers a simpler way to drop this into place on an existing view controller.