Hulu and its owners, three of the big broadcast TV networks, want to bring some version of the Web video service to Apple’s device.

But the most likely scenario is one in which access to Hulu on the iPad comes as part of a subscription package, multiple people familiar with the company tell me.

Hulu has been free for Web users since it launched in 2008. But its broadcast owners–GE’s (GE) NBC Universal, News Corp.’s (NWS) Fox and Disney’s (DIS) ABC–have repeatedly said they want to introduce some sort of premium version.

Depending on who you talk to, the pay service is either supposed to help the money-losing Web site turn a profit or compensate the networks for the eyeballs and dollars Hulu is supposedly siphoning away. Or both.

The problem is figuring out a way to keep the existing site free while adding new bells and whistles that consumers pay for. One idea the company and its backers like: Turning Hulu from a “one screen” service–one you’re only supposed to watch on your computer–to a “three screen” offering by adding support for TVs and mobile devices.

“Just three screens alone is pretty enticing,” for consumers, says an executive at one of Hulu’s parent companies.

If you want, you can hook up your computer to your big-screen TV with a cable and watch Hulu that way. But Hulu hasn’t aligned itself with devices and software that make the process easier, as Netflix (NFLX) has. Meanwhile, there’s no Hulu for devices like Apple’s iPhone, even though rival YouTube, owned by Google’s (GOOG), loves smartphones.

And while you could argue that the iPad isn’t necessarily a mobile device, since 3G Internet access is an optional feature, Hulu and the broadcasters that own it are likely to classify it as one. Like many other content owners, the video service sees the device as an opportunity to charge for something it has been giving away on the Web.

All the sources I talked to cautioned that Hulu and its owners had yet to agree on a definitive plan for a premium service. And this needs to be resolved before they can tackle device-specific issues.

“It’s a tricky balancing act that we’re trying to fine-tune before we go out,” one source tells me. “Everyone’s concerned about making a strong offering at a good price, and not undercutting the existing business.”

And if Hulu does decide to head to the iPad, it will involve some work for both engineers and lawyers.

Hulu, like almost all Web video, uses Adobe’s (ADBE) Flash, which is a no-go for the iPad, so that would require a workaround of some sort. It’s doable, but not a snap.

And if Hulu decides to define the iPad as a mobile device, it would also need its content owners to grant it mobile rights, which it doesn’t actually have. Again, doable. But the broadcasters are already making money from other mobile services, like Verizon’s (VZ) V Cast. So they have to tread carefully.

All of which makes it very unlikely that you’re going to see Hulu on the iPad when it begins shipping at the end of March, no matter how badly Apple (AAPL) would love it.

A rumor that the service would launch alongside the iPad surfaced in the wake of Steve Jobs’s New York media tour earlier this month. And I don’t think that’s a coincidence. But I don’t think that makes it so, either.

Philosophical questions for the ages, these, and Verizon will get an answer to the second tomorrow. Because this morning it tossed a release into the iPhone whirlwind, seemingly for no other reason than to let us all know that its stores, like AT&T’s, will be open late tomorrow, too. Course if you stop in at one looking to buy an iPhone, you’ll be sorely dissapointed. And a V CAST-capable phone, even one “packaged for immediate fun” by Verizon, will likely come as precious little solace if you end up wait-listed for an iPhone – although you will be in good company. At Apple’s all hands meeting this afternoon, CEO Steve Jobs said that all full-time Apple employees will receive a free 8GB iPhone at the end of July, after initial consumer demand dies down.

MobiTV, from MobiTV Inc., www.mobitv.com, gives people a way to watch television on their cellphones.

For lovers of portable video, the arguments in favor of TV on phones are speed and convenience. Rather than waiting to download movies, video podcasts and TV shows to a computer and then to transfer them to a portable player like an iPod, some would rather see current, live content streamed onto the device they already carry — their cellphone — whenever they want, wherever they are.

Live TV on cellphones isn’t new. We first tested it in 2004. But it was awful then, choppy and almost unviewable, because the cellular networks were too slow and the phones were too wimpy. So I decided to try it again.

Many cellphones are capable of displaying streamed television using built-in services, but few people are aware of these capabilities and not every phone will work as well as the next. The best results are delivered on devices with good quality screens that can retrieve and display the content using high-speed networks.

I used a mobile content-streaming service called MobiTV on three phones serviced by two carriers, Sprint Nextel Corp. and AT&T Inc.’s Cingular Wireless, watching a variety of shows on screens smaller than the palm of my hand. Monthly usage for watching cellphone TV with these two carriers costs about $25 and $30, respectively, on top of your voice plan. MobiTV is compatible with more than 150 handsets, offering roughly 40 channels — about half of which show live content like that found on your home TV.

All in all, MobiTV offers a fun and simple solution for people seeking TV on the run. High-quality images appeared on screen just moments after I opened the MobiTV application and an on-screen guide labeled each channel. TLC, ESPN, The Discovery Channel, The Oxygen Network and major news channels are entertaining enough. And though my eyes hurt after 30 minutes of watching such a small screen, I only ran into a few other snafus: on-screen images disappearing while audio continued, certain channels cutting out and lips moving out of sync with audio. In more cases than not, these instances were rare or corrected themselves in seconds.

Other carriers offer video clips that might easily be confused with MobiTV Inc.’s technology. Verizon Wireless, for example, offers its V Cast service. But V Cast requires that you download clips onto your device. Sprint and Cingular also offer video-on-demand options. But the MobiTV service streams content onto your phone, showing it just about a minute later than the same content on live TV.

If you don’t use Sprint or Cingular and you’d like to download MobiTV to your standard cellphone, or to your Palm or Windows Mobile smart phone, you can do so through third-party vendors like Handango.com; these options can be found on www.mobitv.com. Vendors charge about $10 a month on top of any data charges that you might owe your carrier.

MobiTV’s service includes a channel guide.

Sprint and Cingular encourage you to buy an unlimited monthly data plan in addition to your voice plan if you’ll be watching TV on your cellphone. Sprint calls its live-TV service Sprint TV Live — though it’s really MobiTV beneath the covers — and offers TV-inclusive data plans for $15, $20 or $25. These return 8, 13 and 25 channels respectively. Sprint’s exclusive content includes the NFL network. To further confuse matters, you can also buy stand-alone Sprint TV Live on top of those three data plans; it costs about $10 monthly. Cingular charges users about $20 for its unlimited data plan plus $10 for MobiTV usage. This carrier keeps the MobiTV name.

MobiTV worked relatively the same way on all three handsets with both carriers: two Windows Mobile devices, the Sprint PPC-6700 and Cingular 8525, and a basic cellphone, Samsung Electronics Co.’s SGH-A707 with Cingular’s 3G network. In my tests, MobiTV came pre-loaded on the devices, letting me simply select it from a list to start watching streaming content.

On the Cingular 8525, a smart phone running the Windows Mobile 5.0 operating system, I browsed through a guide until I found The Oxygen Network. The Isaac Mizrahi Show, not a favorite of mine, was just ending. It was followed by a quirky game show called “Can You Tell?”

MobiTV streams two types of programs: Live and Made for Mobile. Live shows are like those on your regular TV though slightly delayed and with different commercials in the local ad slots. I watched MSNBC’s “Hardball With Chris Matthews” using MobiTV and my regular TV, and an interview with Mia Farrow started about a minute earlier on my TV than it did on my mobile device.

Made for Mobile channels include special MobiTV content, such as music-video channels, or content for certain channels that MobiTV stitches together to show in a better format for mobile. The latter is the case with ESPN; in 15 minutes, I watched clips about football, Nascar, baseball, boxing and basketball with only a few quick commercials. In these snippets, however, lips weren’t synched with the audio.

I often opted to view content in full-screen mode, which, in 10 seconds, alters the image to take over the whole screen in horizontal view. A few times, while watching full-screen view, my on-screen content froze and had to restart in the regular view.

MobiTV says that using its service to watch programs saps battery at a rate equal to that of voice calls.

People who use digital video recorders at home to pause or rewind live TV will be disappointed to find you can’t do that with MobiTV. The company is hoping to offer these capabilities in the future. But because of the smaller screen, you probably won’t want to watch your mobile screen for as long as you would a regular TV, reducing the need to pause and rewind.

MobiTV’s services will never replace your home-entertainment center experience. But the ability to watch TV on your phone is a great way to stay plugged into news and entertainment. Just be sure that you’re using a fast network and a generously sized screen.

– Edited by Walter S. Mossberg