Google's Eric Schmidt has given up his seat on Apple's board of directors, closing a partnership that paved the way for the success of Apple and Google in the mobile space. Neither company could have risen so far, so fast without the other. Apple made the Google Maps pushpin and the YouTube skateboarding dog iconic of the iPhone's utility, simplicity, and flexibility; the iPhone was, in effect, the first Google phone.

Google Maps and YouTube, with Safari, rounded out the iPhone's killer app trifecta. That Apple gave Google equal billing was unprecedented, and I think that relationship set Google up for its current role as go-to software supplier for handset makers and wireless operators, which in turn enabled Google to move into the mobile cloud business with Gmail, Google Talk, Google Sync, Google Voice and voice search, Google Latitude, and other services.

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Every new smartphone, regardless of platform, is now expected to hit the streets prewired for Google services, and I think that the speed with which a mobile platform takes on new Google services, and new releases of Google client-side apps, will partly determine that platform's success and customers' satisfaction.

The iPhone stands apart from Google's other mobile platforms in its lack of support for third-party background applications, making the iPhone a disadvantaged peer among growing numbers of devices connected via Google's cloud. iPhone clients for Google Talk and Google Voice are not in the offing, and with this restriction, it's also impossible to make Google's Latitude location tracking service work unless the Latitude site is active in Safari. Google Sync, being based on the Microsoft Exchange ActiveSync protocol licensed and implemented on the iPhone and for which a systemwide background listener is already in place, is an exception. I think that even if Google Sync couldn't hitch a ride on iPhone's Exchange client support, Apple would have made an exception to sync with Google's free cloud. But that was then.

While Google was in the catbird seat as a rare Apple software partner and insider, other exceptions of the sort necessary to keep iPhone on par with other Google-enabled mobile platforms could be expected. I can't imagine how -- with Google being a core platform enabler for all of Apple's mobile competitors, as well as Android's direct competition with iPhone and the looming threat of the Chrome OS in the Web-centric desktop arena -- Apple and Google could remain as tight as they were on iPhone's launch day. Just the same, Apple and Google are two of a kind among innovators. I wonder what we'll miss out on now that they have reasons to keep secrets from each other.

As it stands, I can see Google fleshing out its iGoogle client, downloadable from Apple's App Store, to act not only as a launcher but as a sort of alternative Home screen. What goes on under iGoogle's covers is up to Google, as long as the client doesn't run afoul of Apple's policies. Those policies prohibit telephony over the cellular data network and loading of executable code modules, creating barriers to Google products like Voice and Gears even if Google prevails in turning iGoogle into iPhone's other Home screen.

Apple's gazillions of Developer Program participants, most of them working in native code, give Apple an advantage that other platforms can't match, even with a push from Google. If Google envy strikes in the form of some future feature denied to i 

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