This was mentioned in the article of course, but it bears repeating. I don't think there's any way around doing extra work when you target another platform. The UX guidelines for the Android and iPhone are different and you want to work within those guidelines.

HTML5 may be a way out of this, since the user is in a different contextual frame of mind, but if you want folks to think it's an "app" then you should still be aware of (and target) specific UX recommendations.

I agree. While having to design once for both platforms could be great for the designer, it isn't for the user. Following the guidelines of the specific platform cut enormously the learning curve and makes the use of the app more natural. Just think about all the fuss about the three buttons in iTunes 10 placed vertically instead of horizontally, moving away from the standard position.

I'm inclined to think that eventually html5 "apps" will largely displace native apps for the same reasons so many desktop functions have migrated to the web. The porting issues this article describes are just some of the many disadvantages of native interfaces.

I'm inclined to agree with you. However, there are advantages to leveraging the user's current framework of understanding. Additionally, web-apps often use native web-browser controls.

When I look at many of the example differences between Facebook's app in iOS and Android, some appear to be design decisions that don't have anything to do with native interfaces. For example, I'm not totally familiar with Android, but I'd bet pull to refresh could be implemented if needed. Likewise, tapping the Facebook title in iOS also brings up the application menu-the little block button is redundant.

How do Html5 apps get paid? If those are integrated into the Markets, then there will be a boon to them. Otherwise, it will be just like the Flash apps.

You can use Google's Chrome Web Store to sell HTML5 apps. For info, how to integrate with your apps, see: http://code.google.com/chrome/webstore/docs/index.html

Looks like an interesting article. It's too bad some of the text is hidden behind ads (Chrome 6 beta/Win7).

Same problem here. Safari for iPhone.

Actually "readability" made it work.

Not if you make a slick html5 mobile version instead.