In what looks to be an about-face, Apple has begun to approve browsers for the iPhone and iPod Touch made by other companies. A few basic restrictions seem to exist, but this could pave the way for mobile versions of Firefox and Opera to appear on the iPhone. Updated with info from Opera.When Apple first announced iPhone 2.0 firmware and the Apps Store, it laid down some pretty clear ground rules. Chief among them: No applications that duplicate the functionality of preloaded, Apple-developed applications, such as the Safari browser.

The iPhone is a capable browsing device, though the version of Safari on the iPhone has limitations, among them the inability to play Flash content. Opera is well-known for its adept Opera Mobile and Opera Mini browsers. Versions of Opera -- and Firefox -- that work on the iPhone could provide relief from some of Safari's shackles.

Until now, that wasn't considered a possibility. Just recently, Apple has begun to approve Web browsers from third parties. A quick check of the iPhone Apps Store shows at least four new browser applications. According to MacRumors, the Edge Browser provides no loss of screen real estate in the address of navigation bars. Incognito permits browsing without leaving a trace. Shaking Web adds some accelerometer-based functions. WebMate:Tabbed Browser makes its name by offering tabbed browsing on the iPhone.

These may not be earth-shattering new browsers, but they are a start. It would be fantastic if Apple removed some of the remaining SDK restrictions and permitted developers (hint, Opera and Firefox) to make full versions of their browsers for the iPhone.

I e-mailed Opera for comment first thing this morning, but have yet to hear back from them. I'll update this article once I do.

Update:

Opera spokesperson Thomas Ford said in an e-mail, "We cannot confirm if full, third-party Web browsers will be allowed on the iPhone. What has been released thus far are skins on top of Safari, so we are not certain if Apple has relaxed its policy. Our goal remains, as always, to make our browser available on as many platforms as possible. However, Opera is at this time not available for the iPhone."

Update 2:

Turns out the new browsers aren't full browsers at all. ZDNet's Matthew Miller reports, "These 'browsers' are basically different skins for the Webkit browser engine on the iPhone." In other words, they enhance the functionality of the existing Safari browser.