Ian Fogg - Mobile Web vs Applications/Widgets.

"The number of mobile platforms in the market now or soon is, and I'm sure I'm not listing all of them:

• Nokia's Series 60.
• UIQ.
• Windows Mobile Professional (v6) / Window Mobile 5 Pocket PC.
• Windows Mobile Standard (v6) / Windows Mobile 5 Smartphone.
• J2ME.
• Brew.
• Google Android.
• Apple iPhone / iPod Touch (announcement due any day now on the SDK).
• Palm OS.
• Yahoo! Go Widgets.
• Nokia Widsets.
• Blackberry.
• Nokia Internet Tablets (OS2008 vs OS2007 etc).

And, worse, within most of the above handset platforms, there are different versions of each platform which leads to issues for application developers. Plus, many users will have no idea what platform, precisely, is on their phone as the mobile industry chooses not to communicate those details, and so users have little clue about which applications will work on their phone model."