Why would Yahoo build a browser?

Particularly if browsers and operating systems – especially mobile OSes – are becoming more tightly integrated. Well, Yahoo’s Axis is a browser app on an iPad and an iPhone, but it’s more like a search plug-in on the desktop. In fact, if it has any success on the iPhone, it will be as a search alternative. And although it looks spiffy, search results presented visually on a small phone screen don’t seem very practical. Axis is getting good reviews, and gives a great tablet demo. But although Yahoo is talking about advertising potential, it’s not actually serving up any ads yet. Even on the tablet, where it might be able to charge a premium. It’s just leaving money on the table there and with the desktop plug-in. That or robbing search partner Bing.