The mobile marketplace is a cruel world. Users often download an application on impulse, try it once, and may never open it again if their first impression is negative. You should aim for excellence and simplicity. Define your application in one sentence. Find your niche. Make it unique, if not in concept, then in execution.
Also, you should analyze mobile consumption. An application is often only used for a few minutes at a time. Tasks should be completed quickly or in incremental steps saved on the device. Whatever you do, do not attempt to replicate your existing website. Instead, adapt it for mobile or create a companion application.
The APK File
The default system icon is an Android-green icon. Icons need to be 36×36-, 48×48-, or 72×72-pixel PNG images. They are used for low-, medium-, and high-density screens, respectively.
You should make your icon stand out, while clearly identifying your application. Google provides guidelines on how to make icons, and provides a Photoshop template, at http://developer.android.com/guide/practices/ui_guidelines/icon_design.html.
In Flash Professional, go to File→AIR Android Settings→Icon and browse to the icons on your computer.
In Flash Builder, create a directory called icons in the src folder, and place your icons in it. Right-click on your project and select Properties. Then select ActionScript Build Packaging→Google Android→Package Contents and select the icons folder if it is not already selected.
In other tools, add a node to your application descriptor file as follows:
<icon>
<image36x36>icons/36.png</image36x36>
<image48x48>icons/48.png</image48x48>
<image72x72>icons/72.png</image72x72>
</icon>
Alternatively, if you are using the command line, place all your icons in a folder called icons and add it to the end of your statement:
AIR-sdk-path/bin/adt -package -target apk -storetype pkcs12
-keystore yourCertificate.p12 hello.apk Main-app.xml Main.swf icons
Publish your application one last time. Change your application to release mode if it is in debug mode. In Flash Professional, select File→AIR Android settings. Under the Deployment tab, for “Android deployment type,” choose Release.
If you are publishing from the command line, verify that the target is apk:
AIR-sdk-path/bin/adt -package -target apk -storetype pkcs12
-keystore yourCertificate.p12 hello.apk Main-app.xml Main.swf