Why can’t mobile apps have URLs?

Dave Winer laments that mobile apps are not universally addressable via a locator like a URL.

Actually, they are, it’s just underexploited. For example, this little radio app allows me to deep-link specific radio stations as tiles on my (Win Phone 7) home screen.

Guess what? The tile has a URL, pointed to a specific place in the app. Now, I haven’t dug deeply enough to know about the security boundaries, but it seems to me it would be a small step to allow the app to register a namespace on the phone (app://appid) and expose endpoints to any other app.

This seems like a nice way to bridge the gap between the advantages of phone and web. iPhone allows protocol handlers which are the same idea, putting the namespace at the front of the URL.

(Of course, URLs would need to be managed just like public, web URLs — you’d want them to be stable, and deliberate about what’s exposed.)

A future of on-device linking may be closer than we think.