According to this and this, the Apple iPhone can not run third party applications. Even if eventually Apple introduces a Javascript Widget programme, this is not enough in my opinion. Without a native SDK, this thing is simply a high-end feature phone, as I wrote in my analysis today. Other things are missing too from the device (ok, it’s a v1.0 release still), but the no-SDK business is a big deal. Without it, the iPhone can not be called a “smartphone”.