Google has given Gmail users that own Apple iPhones or Microsoft Windows Mobile devices push email.

That means that email messages sent to Gmail accounts will be received immediately on mobile devices rather than having to be summoned at 15 or 30 minute intervals by the device.

The push functionality will work with the iPhone and with Windows Mobile devices. Google has had some conflicts with Apple in terms of getting apps approved for the iPhone.

The previous relationship of cooperation has disintegrated into a head-on rivalry. So, Google didn't bother trying to work through Apple to make the push functionality work. I

nstead, the Gmail push capability is a modification that leverages the push functionality Apple built into the iPhone for Microsoft Exchange.

Apple is familiar with the importance of push capabilities for email - particularly Microsoft Exchange email. The lack of Exchange integration and push functionality in the original iPhone were seen as some of the biggest factors slowing its acceptance as a business tool. Apple resolved those issues with the release of iPhone 3.0.

The solution that Google implemented requires setting up an Exchange email account on your iPhone or Windows Mobile device, but using your Gmail credentials. With the updated Google Sync, you can now get your Contacts, Calendar, or Gmail, or any combination of the three pushed to your mobile device.

The Google Sync workaround works, but not if you already have an Exchange email account and you would also like to get your personal Gmail account pushed to your mobile device. You can only have one Exchange account set up at a time.

For users who were hoping to get their Gmail messages pushed instantly to their iPhone or Windows Mobile device in addition to their Exchange account, you're out of luck for now.

But, for small and medium businesses that don't have Microsoft Exchange, the new capability represents a significant maturing of the Gmail service and helps these smaller organizations compete on a more even playing field with their larger enterprise peers.

Aside from its battles with Apple, Google's primary rival is Microsoft. Providing push capabilities for Gmail will help Google compete more directly with Microsoft Exchange, just as Google Docs goes head-to-head with Microsoft Office and Office Web Apps, Chrome seeks to compete with Internet Explorer (and Apple Safari), Android battles against Windows Mobile, and the upcoming Google Wave endeavors to provide an alternative to Microsoft Unified Communications.

Google is marching forward in its evolution from a search engine provider and is working to establish dominance in every conceivable aspect of the Cloud. Taking on both Apple and Microsoft simultaneously is no small feat, but Google seems to be winning its share of the battles so far.

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