Lessons Learned in the Windows Phone 7 Marketplace

The following are a few of the things I learned during the development process and submitting a first application to the Windows Phone Market Place. Hopefully they can be of some help to others.

Application Name

If your application name is more than about 15 characters, the whole application name may be truncated on the various WP7 screens. This is also true in the thumbnail view in the Market Place. Note how the text fades to white toward the right side of the name in the screenshot below.

Iconography

Graphic design in the consumer market space is a necessity. Your icons are displayed immediately adjacent to other professional designs - regardless of app quality.

Application Icons

Initially I created a 31px application icon. I think that was the size used during the RC or beta version of Visual Studio Express for Windows Phone 7. The following are the default icon sizes for Windows Phone 7 application certification:

• ApplicationIcon.png 62px (transparency allowed)
• Background.png* 173px (transparent allowed)

* Tip: don’t put the application name in this image (or any important cosmetic detail at the bottom) as the Application title text from the Visual Studio property page will be rendered on top of the 173px icon near the bottom of the image (see the “Start Screen” in the screen shot below).

The following is a composite image containing multiple screen shots:

• Phone Windows menu screen (left)
• Visual Studio project properties, application tab (center)
• Phone Start screen (right)

Note in the image where the text is displayed and which images are used on the various app screens. Click the image for full size.

Market Place Icons

The following square icons (without transparency) are required for display in the Market Place:

• 99px
• 173px
• 200px

WP7 application screen shots can be uploaded to showcase key functionality.

• 480 x 800px screenshots
• vertical orientation for upload
• set zoom level on emulator to 100% for correct screenshot resolution (need a high enough resolution monitor to capture the screenshots. 1024X768 is not good enough)

Marketplace Detailed description

I copied my description from a website where the application is described. I’m not sure I would do that in the future as it did not display properly on the app hub submission page (note the incorrect text wrapping at the end of the lines. There doesn’t appear to be an option to edit the description without re-submitting the application.

I was pleasantly surprised the text looked correct when my application was certified as approved, but I don’t know if the person testing the app corrected the description text formatting during prior to approval/publishing.

Another developer had the misfortune of an unfortunate example using a bullet list format.

Submission and Certification

I submitted my application to the App Hub on a Sunday evening and it was certified by the following Wednesday morning. It was accepted on the first submission, but the feature set (and graphic design) was kept intentionally simple in the first version.

Windows Phone 7 Testing a Date Change in the Emulator

I wrote a WP7 application that stores a bit of data based on today’s date. Tomorrow when the date changes, yesterday’s data gets cleared out to start fresh. Before submitting the app to the App Hub I needed to test whether it would work as expected when the date changes. At the time, I didn’t have an actual Windows Phone 7 for testing so I used the Emulator. The testing process didn’t work out quite as I expected.

Happy Path

1. Load Emulator
2. Deploy app to the emulator
3. Run app
4. Click some buttons that store today’s data
5. Change the date on the development box (assuming that is where the emulator gets its current date)
6. Click the windows key to unload the app
7. Return to app (which should have a different date since I changed the date on the development box)
8. The app data should be empty because it is a new day

Fail

There were a few misconception to the above.

• It appears that the emulator loads today’s date when the emulator starts up, because it didn’t change when I changed the date in my development environment.
• When you click the back button it unloads the application and you lose the data stored in Isolated Storage.

Fix

Replace steps 5 & 6 in the above “Happy Path” with the following steps to effectively test the date change:

1. Click to the System Settings page in the Emulator
2. Click “date & time”
3. Toggle the “set automatically” slider to Off
4. Click on the date in the date field
5. Change the date to a different day
6. Click the windows key and left arrow icon to see the app in the menu.