Hello there, my name is Frank Prengel, and I’m a technical evangelist at Microsoft Germany, helping the Windows phone and Marketplace teams establish Windows Marketplace for Mobile in my country. Since I work with the German developer & ISV community, let me share with you some thoughts from a local perspective – they may help you develop for Marketplace, especially if you live outside the US.

Let’s first remember that Windows Mobile has always had a very active developer community, and that it gives you freedom in how software is developed and distributed. There are more than 20,000 Windows Mobile applications today which you can get and install from Web sites, software portals, forums, etc. – provided you are a tech savvy person, and you know how to do it. With Windows Mobile 6.5 we have begun addressing non-tech savvy consumers as well. This is exactly why we introduced Windows Marketplace for Mobile as an easy way for people to find and install additional software on their new Windows phones.

If you are a developer, this means one thing for you: an additional great opportunity to potentially reach millions of new customers. Windows Marketplace launched with commerce in 20 markets as well as developer registration support in 29 markets, more than any other app store at launch. It offers credit card as well as mobile operator billing, and self-serve refunds of certified apps. It now supports Windows Mobile 6 and 6.1 and even allows for browsing and purchasing apps from the PC, with over-the-air synchronization to the user’s Windows phone. If your goal is to expand your business or the reach of your software, you should take the opportunity to join. For more information on the recent Windows Marketplace updates, including availability on 6 and 6.1, accessibility to browse and purchase apps from the PC and antipiracy protection benefits for developers, check out Todd Brix’s blog post at the Windows Mobile Developer Blog, and Eric Nelson’s post at the Windows Phone Blog.

As with every retail marketplace, there is a bit of administrative work involved. Windows Marketplace for Mobile is a new service and a fresh approach that improves frequently with feedback from the developers and ISVs we work with. We are committed to continually improving the entire experience as we learn more about developer and customer needs and behavior. (If you find that Marketplace is not the right distribution channel for your business model, after all, you can of course use any other channel, such as those mentioned above, as they continue to be available. Windows Mobile means freedom of choice.)

If you are in the US, signing up and getting apps certified should be pretty straightforward by now. In other countries there may be additional steps related to the business and financial processes involved. There also is localization work to be done when you want to submit products to several markets, as the application needs to be localized in the proper language (including the screenshots and descriptions). If there are any questions during this process, your first support resource is the Windows Marketplace help page. You can also use the contact form in your Windows Marketplace portal, and ask for help or information. Then, we have a dedicated forum where team members try to answer your questions as quick as possible.

Beyond all that, in some countries there are additional dedicated resources that you should know – let me take Germany here as an example: We have a dedicated Windows phone blog with news and a contact form for questions, we have our local Windows Mobile Developer Center on MSDN, a Twitter channel, a comprehensive introductory document on Windows Mobile development, a webcast series – we even have an exciting local developer contest which complements the global one!

You see, there are a lot of great resources that should help you get started with Marketplace. Don’t miss this great opportunity to expand your mobile business. Good luck!

Frank

The Windows Marketplace for Mobile client provides users a streamlined experience to purchase and install applications on their Windows Mobile 6.5 devices (coming soon for 6.1, and 6.0).

As you will notice when installing applications, the user interface is different from the typical CAB file installation (see below) perhaps you are used to.

It is very important that the Marketplace install experience be uniform and streamlined. To keep it this way, no custom UI (errors, prompts, informational messages, etc.) should be displayed during installation or uninstallation.

If you absolutely must display custom UI, there are some things you should know about the Marketplace client.

The Marketplace client achieves a streamlined experience by suppressing the normal user interface, displaying a client specific progress bar and providing feedback when the installation has completed. This can cause problems for applications that have custom prompts implemented in the setup dll. For example, you may want to prompt the user to start your application after installation has completed. This is easily done by adding the appropriate MessageBox prompt to the Install_Init export of your setup dll. However, there can be problems with this.

The foreground display of your MessageBox or other custom UI, depends on knowing the window handle of the calling process. When your application is installed with the Marketplace client, no window handle is passed to your setup DLL’s exported functions. This can cause your custom UI to not be displayed in the foreground. This causes confusion for the user since it looks like the installation is still running, but there is no UI feedback. The only recourse for the user is to use task manager to locate the prompt window and select it to bring it to the foreground. This is a very poor user experience. 

You can resolve this by using the MB_TOPMOST | MB_SETFOREGROUND flags when calling MessageBox or WS_EX_TOPMOST when creating a window for custom UI.

Have you tried the Marketplace client yet? No? Don’t have a 6.5 ROM update or device yet? No problem. Download the Windows Mobile 6.5 standalone emulator images here. These come with a fully functional Marketplace client you can download and install apps with.

Hope this helps.

Mike

The Windows Marketplace for Mobile is off to a great start since its release October 6th. One issue that has tripped up a few developers submitting their applications has been the use of internal registry keys used to determine the location of the application. Some clever developers have discovered that there is a list of installed applications stored in the registry under: HKEY_LOCAL_MACHINE\Software\Apps. Under the application name, you will find the directory in which the application has been installed. For example:

HKEY_LOCAL_MACHINE\Software\Apps\Company Application Name
InstallDir=”\Program Files\Application Name”

a similar list can be found here:

[HKEY_LOCAL_MACHINE\Security\AppInstall\Company Application Name]
InstallDir=”\Program Files\Application Name”

Since Windows Mobile does not support the concept of a current working directory, this has been one way to determine where the EXE is running from. A better approach, that is not dependant on these registry keys,  uses the following code (See Chistec’s blog post):

GetModuleFileName(GetModuleHandle(NULL), pszFullPath, MAX_PATH); 

For managed code (See Chistec’s blog post):

using System.Reflection;

private string GetApplicationExe()
{
  // Determine the full path to the application executable
  return Assembly.GetExecutingAssembly().GetName().CodeBase;
}

You can then parse out the application path from the returned file name.

So what is wrong with using these undocumented registry keys? When your application is installed by the Marketplace client, it creates these registry keys, but not with the names you would expect. Therefore, if your application is relying on any of these keys, if will fail to find them, because they will not exist.  This has tripped up a few developers because this issue does not surface unless you install the application after it has gone through the Marketplace ingestion process. (The processing of your application after it has passed certification testing.)

To summarize, if you need to get the directory in which it was your application was installed, use either the native or managed APIs above. Also, make sure you are not using either of these undocumented registry keys.

Thanks,

Mike