The iPhone isn't the only Apple product getting a July makeover. Apple is also revamping .Mac, its collection of Web-based tools. Starting next month, .Mac gets new applications, a new focus on mobility, more iPhone-friendly features, and a new name--Mobile Me.

We've watched Apple's Worldwide Developers Conference keynote, talked to Apple executives, and perused the materials on the company's Web site to get a better grasp on this new online service. Here's what to expect when Apple throws the switch, and .Mac transforms into MobileMe.

What is MobileMe?

MobileMe replaces Apple's .Mac service. It retains many of the features of .Mac--such as online storage and Web page-hosting, just to name a couple examples--but the revamped service places a greater emphasis on synchronizing information between your various devices. MobileMe users will be able to take e-mail, contacts, and calendars and share them seamlessly between a computer at work, another computer home, and a mobile device like the iPhone or iPod touch. And the key to all of this is synchronization and push technology.

Push technology? Sounds buzzwordy. What does "push" actually mean?

Push services are a type of Internet communication in which a server sends out--or "pushes"--data on its own, without any prompting from the end-user. For example, with push e-mail, messages are delivered to your inbox as soon as they're sent. There's no need for you to tell your e-mail client to check and see if there are any messages waiting to be downloaded from the server. (That would be a "pull" service, and it's how most e-mail currently works on the iPhone, incidentally, although the iPhone does support Yahoo mail's push IMAP mail technology today.)

Push services are particularly critical in business settings where users want the data on their mobile devices to be current and up to the minute. In the corporate world, that usually means an Exchange server coupled with Microsoft's ActiveSync synchronization service--corporate users can access e-mails, appointments, contacts, and other data on a company's server, and new information is pushed out to a user's mobile device. In fact, Apple has licensed ActiveSync specifically to make the iPhone more attractive to enterprise customers using Exchange servers.

MobileMe works on the same principle--you access the same e-mail, contact, and calendar information whether you're on a Mac or PC, iPhone or iPod touch. (Hence, the "Exchange for the rest of us" theme that Apple's marketing team has adopted.) And you don't have to take any action to get that information onto your device--whenever there's a change, it gets pushed to you and your assorted devices.

OK, so how does it actually work?

With MobileMe, e-mails, calendar events, and contacts are stored on a secure online server, which Apple calls "the cloud" in its video guided tour of MobileMe. That's a jargony way of saying that the information is stored in a place you can reach, via a network connection, regardless of where you are and what device you're using.

Update a calendar on one device, and with MobileMe, the new event will appear on all your devices, such as the iPhone.

So let's say you add a new appointment to your personal calendar from your Mac. That appointment is received by the secure online server and is then pushed back out to all your other devices: for instance, the appointment might pop up on your iPhone's calendar right away.

It works in reverse, too--changes on one device are sent back to the server and instantaneously updated on your other devices. Add a contact to your iPhone? It'll appear in Address Book on your Mac. And photos are part of the mix, as well. If you update a contact's photo on one device, that change will be reflected on all other devices.

What programs does MobileMe work with?

If you're using a Mac--and because you're reading this article, we assume that you are--MobileMe will work in conjunction with Mail, Address Book, and iCal. For Windows users, MobileMe works with Microsoft Exchange on either Windows XP or Vista. And, of course, the online service works with the mail, calendar, and contact applications on either the iPhone or iPod touch.

It's unclear if there will be some framework to allow other Mac programs, such as Microsoft Entourage, to sync with MobileMe. Apple says the service was specifically designed to work with Mail, Address Book, and iCal on the Mac.

And that's all there is to it?

Well, no--MobileMe is an online service, so there's a Web component, as well. The mail, contact, and calendar services all have online versions at Apple's Me.com Web site. (Currently, the Me.com address redirects you to an information page about MobileMe; presumably, when the service comes online in July, the Web page will go live.)

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