Which icon sizes should I use in my application?

I find an article to answer the question: here
Summary of the article:

If you are creating a single .exe that is designed to run on all Windows Mobile devices, use an application icon with these sizes:

• 16x16
• 22x22
• 32x32
• 44x44
• 64x64

If your .exe is only designed for "Pocket PC" devices, use an application icon with these sizes:

• 16x16
• 32x32
• 64x64

If your .exe is only designed for "Smartphone" devices, use an application icon with these sizes:

• 16x16
• 22x22
• 32x32
• 44x44

I advise a FREE icon editor, which can generate all needed sizes from one picture:
http://icofx.ro/