"Every framework has advantages and disadvantages," he says. "You can't make blanket statements that one is better than the other; you have to qualify it."

He has extensive background in Windows development, and writes , where he's currently writing about his Windows Phone 7 experience. (He has co-authored several books, including . Hoffman also has a at Amazon's Web site.

But until recently he's also been editor-in-chief of Sys-Con's iPhone Developer's Journal, and does contract work writing iPhone apps. He has presented at Apple's Worldwide Developer Conference, comparing programming for iPhone and for Microsoft .NET Compact Framework.

We caught up with him to ask him his impressions of Windows Phone 7 (WP7) and the differences and similarities between that platform and iPhone.

Given your background, how does WP7 stack up against iPhone?In the market of high-end mobile applications, iPhone has had a monopoly until now. If you have to choose a target device [for you applications], you choose the one with the most users. The iPhone has that.