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;
- Install OSx86 (aka iATKOS / Kalyway) on a second partition/disk and dual boot.
- Run Mac OS X Server under VMWare (Mac OS X 10.7 (Lion) onwards, read the update below).
- 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
This arstechnica article describes the basic steps:
Start by visiting the program portal
and make sure that your developer
certificate is up to date. It expires
every six months and, if you haven't
requested that a new one be issued,
you cannot submit software to App
Store. For most people experiencing
the "pink upload of doom," though,
their certificates are already valid.
What next?
Open your Xcode project and check that
you've set the active SDK to one of
the device choices, like Device - 2.2.
Accidentally leaving the build
settings to Simulator can be a big
reason for the pink rejection. And
that happens more often than many
developers would care to admit.
Next, make sure that you've chosen a
build configuration that uses your
distribution (not your developer)
certificate. Check this by
double-clicking on your target in the
Groups & Files column on the left of
the project window. The Target Info
window will open. Click the Build tab
and review your Code Signing Identity.
It should be iPhone Distribution:
followed by your name or company name.
You may also want to confirm your
application identifier in the
Properties tab. Most likely, you'll
have set the identifier properly when
debugging with your developer
certificate, but it never hurts to
check.
The top-left of your project window
also confirms your settings and
configuration. It should read
something like "Device - 2.2 |
Distribution". This shows you the
active SDK and configuration.
If your settings are correct but you
still aren't getting that upload
finished properly, clean your builds.
Choose Build > Clean (Command-Shift-K)
and click Clean. Alternatively, you
can manually trash the build folder in
your Project from Finder. Once you've
cleaned, build again fresh.
If this does not produce an app that
when zipped properly loads to iTunes
Connect, quit and relaunch Xcode. I'm
not kidding. This one simple trick
solves more signing problems and "pink
rejections of doom" than any other
solution already mentioned.
Best Answer
It's been my experience that Xcode occasionally gets confused about which signing certificate to use. I got into the habit of quitting and restarting Xcode after any change to the code signing settings (and doing a clean build) to work around this problem.