Blogger Johnny Makkar has started this Google doc that lists only the branded iPhone apps in Apple's store, and lays them out in a pretty, tabular format. It's intended as a resource for marketers and developers, rather than consumers. There's potential for a great crowdsourced resource, if brand managers make sure their own entries here are up to date.
Makkar says he "will also be adding Android, Palm, BlackBerry soon." Johnny, you're an iPhone guy. Stick with what you love. This one spreadsheet is more than enough of a personal contribution to civilization.