RealNetworks' RealPlayer program once defined digital multimedia online -- it was the only way to listen to scratchy Web radio or watch grainy Web video. Today Apple's iPod holds a similar role in the MP3-player market -- it's the gadget everybody seems to want.

Both of these products were recently updated: Apple's newest iPod adds the best design features of the iPod mini, while RealPlayer 10.5 adds the unprecedented feature of iPod compatibility.

The new iPod, the fourth generation of this device (fans are calling it the "iPod 4G" for short), brings fewer changes than its predecessors. From the back and the side, it looks like a fractionally thinner version of the old iPod. From the front, however, you can't miss its new ClickWheel control.

This touch-sensitive dial, which debuted on the iPod mini last winter, puts all the basic controls into one circular interface: spin a finger around its edge to select songs and adjust volume, push the center button to select a song or a menu item, and push the north, south, east and west axes of the dial to select menu, play/pause, forward and rewind commands.

The new iPod also delivers much better battery life. The 20-gigabyte model Apple loaned (its actual capacity was 18.5 gigabytes) lasted for more than 14 hours in both tests, two hours better than Apple's own advertising claims. If only laptops worked this well!

The other changes in this iPod are all minor. A "Shuffle Songs" command in the main menu saves users a few taps of the ClickWheel. You can create and save multiple playlists on the iPod, but these can't be renamed -- you'll have to remember what you put in "Playlist 1" versus Playlists 2, 3 and4. You can also play back audiobook recordings faster and slower than normal.

The iPod 4G comes at a healthy discount from earlier models; the 20-gigabyte model sells for $299 and a 40-gig version goes for $399, both $100 cheaper than their predecessors of the same capacity. They also include the USB 2.0 cable that once sold for $19 extra -- while leaving out Apple's wired remote control, dock and carrying case, each sold for $39 separately.

But with the older iPod models vanishing from store shelves and the iPod mini perpetually back-ordered, the new iPod may be the only game in town.

RealNetworks would like to get into that game. Months ago, the Seattle firm asked Apple to license the FairPlay software that lets people copy songs purchased from Apple's iTunes Music Store to iPods, so that it could offer the same option to its own customers.

Apple turned Real down, so Real set about making its downloads iPod-compatible without Apple's help.

The results are on display in RealPlayer 10.5, a test release for Windows that incorporates the company's new "Harmony" software (www.real.com/harmony/). Beyond being less pushy during its installation (it no longer embeds Real's own bookmarks in your Web browser), RealPlayer 10.5 allows you to move songs purchased from Real's store -- plus most other music files -- to an iPod, just as you might in iTunes.

The Harmony software converts them to a form that an iPod will recognize, without installing any software on the iPod itself.

Getting RealPlayer to talk to an iPod -- I tested it with an iPod mini and a fourth-generation iPod -- involves a little work. It took me two or three tries to get Real's software to recognize each iPod, but once I had coaxed it past that step, the file transfers proceeded without incident each time.

Harmony can also convert Windows Media Audio files (excluding those bought from such online stores as Napster, Wal-Mart and Musicmatch) to an iPod-ready format, although this vastly stretches out song-transfer times.

Harmony is a major achievement -- it lets users play music downloaded from different stores on one device without resorting to intermediate steps like burning the purchased songs to audio CDs and then re-ripping them to a computer in MP3 format.

In other words, Real has made the iPod even more useful.

And Apple is outraged. "We are stunned that RealNetworks has adopted the tactics and ethics of a hacker to break into the iPod," the company sputtered in a statement released last week. Apple suggested it might sue RealNetworks and issued an unsubtle warning to its users: "When we update our iPod software from time to time it is highly likely that Real's Harmony technology will cease to work with current and future iPods."

Apple's iPod product manager, Stan Ng, wouldn't expand on that statement Friday evening, not even to say whether Apple had received any complaints from iPod users about Real's software.

So Apple's get-your-hands-off-our-product stance remains a mystery to me. Throughout its existence, the iPod has benefited from third parties who broke into it to add features, such as calendar and address-book capabilities, that Apple later adopted. I don't recall Apple threatening any of these people with lawsuits. Nor do I remember Apple suing the developers of the software that lets Linux users use their iPods with that operating system.

But if Apple really is that upset about RealNetworks "breaking into" the iPod, it shouldn't get mad -- it should get even. It should update iTunes so it can play songs purchased from Real's online store. Customers can then make their own choice of what program to use, and Apple and Real can compete like any other pair of music retailers.

Living with technology, or trying to? E-mail Rob Pegoraro at rob@twp.com.