iPhone Development: to Objective-C or not to Objective-C ?

When I think of Objective-C, what comes to my mind is a niche programming language for the MacOS and Apple related products. Thus as far as I know this is the only officially supported language to develop products for iPhones, iPods, iPads and so on ....
On the other hand I really what to develop apps that will work in Windows, Linux and MacOS, and for this purpose I see two options:

1) Develop in C/C++ and try to find tools that translate this code to Objective-C and/or MacOS

2) Use Objective-C to develop any kind of application (at least desktop and mobile apps)

Developing portable iPhone apps outside Objective-C

Swig

For the first option, there is swig ( http://www.swig.org/ ) which is a wrapper for C++ to export its classes and/or functions to several languages (Objective-C is a work in progress).
However it doesn´t really solve the problem because there are libraries.

Mono Touch

The Mono Touch ( http://monotouch.net/ ) is probably one of the most interesting project to develop apps for the iPhone without Objective-C. It makes it possible to develop apps with C#.NET. The same Mono project also make it possible to develop apps for Linux. As a consequence, C#.NET could be seriously considered to develop apps for a wide range of platforms. However unlike Mono one must pay to start using it which may not be a problem if you are familiarized with C#.NET.

PhoneGap

Another options is PhoneGap ( http://www.phonegap.com ) which is an open-source framework whose objective is to let developers to write apps with HTML5+CSS+JavaScript and execute it to the different mobile platforms including iOS.

Objective-C as a portable programming language

I recently read about he mechanics and philosophy of Objective-C language and I got quite impressed by its features. It is not just C with classes as I heard before, it is actually a powerful dynamic language. Everything is an object including the classes itself what reminds me of Smalltalk, LISP and Python.

There are also some options to use Objective-C outside of the Apple ecosystem:

GNU Step

As stated in their website ( http://www.gnustep.org/ ) the objective is to create an open version of Cocoa (former NextStep) for several platforms including Linux and Windows.

Besides porting the API this project also comes with several developer tools such as an IDE named ProjectCenter and a GUI code generator called Gorm.

Publishing ClickOnce winforms applications with command-line MSBuild

One of the most interesting characteristics of tools such as CCNet and Nant is the automated deploy. I found many examples of how to publish an application with pre-configured projects with click-one but I wanted to do it different. In order to make the project file cleaner the approach was to remove all click-once configurations from the project(*.csproj) so that command-line MSBuild will take care of publication configuration in a NAnt script. After some full-days of research, I found the solution below. I hope it helps in your project.

<exec program="${dotnetFrameworkDir}\MSBuild.exe">
  <arg value="${basePath}\MyProject\MyProject.csproj"></arg>
  <arg value="/target:publish"></arg>
  <arg value="/p:IsWebBootstrapper=true"></arg>
  <arg value="/p:SignManifests=true"></arg>
  <arg value="/p:ManifestKeyFile=${basePath}\MyProject\MyCertificate.pfx"></arg>
  <arg value="/p:TargetZone=LocalIntranet"></arg>
  <arg value="/p:GenerateManifests=true"></arg>
  <arg value="/p:PublishUrl=${clickOnceDir}"></arg>
  <arg value="/p:Install=true"></arg>
  <arg value="/p:InstallFrom=Web"></arg>
  <arg value="/p:UpdateEnabled=true"></arg>
  <arg value="/p:UpdateRequired=true"></arg>
  <arg value="/p:InstallUrl=http://myPublishUrlAddress"></arg>
  <arg value="/p:TargetCulture=pt-BR"></arg>
  <arg value="/p:ProductName=MyProject"></arg>
  <arg value="/p:PublisherName=MyCompany"></arg>
  <arg value="/p:MinimumRequiredVersion=${CCNetLabel}"></arg>
  <arg value="/p:CreateWebPageOnPublish=true"></arg>
  <arg value="/p:WebPage=${webPage}"></arg>
  <arg value="/p:OpenBrowserOnPublish=false"></arg>
  <arg value="/p:ApplicationRevision=17"></arg>
  <arg value="/p:ApplicationVersion=${CCNetLabel}"></arg>
  <arg value="/p:CreateDesktopShortcut=true"></arg>
  <arg value="/p:PublishWizardCompleted=true"></arg>
  <arg value="/p:BootstrapperComponentsLocation=Absolute"></arg>
  <arg value="/p:BootstrapperComponentsUrl=${bootstrapperUrl}"></arg>
  <arg value="/p:GenerateBootstrapperSdkPath=${pathBootStrapper}"></arg>
  <arg value="/p:UpdateUrlEnabled=false"></arg>
</exec>