????by Michael V. Copeland

????If you were watching Steve Jobs' iPad demo closely Wednesday, you would have seen it briefly as he showed off the device's Web-surfing chops: the blue Lego of death. For everyone who has tried to play Farmville on an iPhone, or watch Hulu on an iPod Touch, the little blue icon is already familiar. It signifies that Adobe's Flash plug-in is not on the device, and that no matter how many times you try to load that game or video it just ain't going to work.

????For those who live their life on the Web, Apple's seemingly resolute refusal to put Flash on its mobile devices (it works just fine on Apple's notebook and desktop computers) is a bit of mystery. Flash has become ubiquitous on the Internet, providing the software environment for tens of thousands of online games, and millions of video streams, as well as those annoying animations that ask if you would like to "skip intro."

????Rumors crop up every time the iPhone gets a refresh that Flash is coming, and then, like some awkward kid passed up at the school dance by the most sparkling student on the planet, Adobe's Flash gets left out. As with all things Apple (AAPL), no real explanation has been made by Jobs or his team as to why they prefer to give Flash the brushoff. "We have regular conversations with Apple," says Adrian Ludwig, Adobe's group product marketing manager Flash platform. "That specific question has never been answered."

????But of course, this being an Apple-obsessed world, there are numerous theories as to why Apple keeps snubbing Adobe's Flash platform. The common theme in all of them: control. By letting Flash onto its devices, Apple cedes some aspect of control, and in the company that Jobs has built magnificently as control freak in chief, that apparently, does not fly.

????For Adobe (ADBE), here are the hurdles the company faces in getting its all-important technology onto the most talked about devices:

????Flash hasn't kept up with the times

????The technology was developed originally as a so-called "runtime environment" in the PC world, and that means it grew up running on Intel's X86 chip architecture. Why that is important in today's mobile world is that most mobile gadgets, including the iPhone and presumably the iPad, use a different chip architecture: ARM. And current versions of Flash have problems running on ARM. "It's a question of balancing power management, performance and memory allocation," says a mobile developer very familiar with the issue.

????Flash is a drain

????Flash looks pretty, but, largely because it's not native to ARM, the technology demands an outsize chunk of the semiconductor's cycles. That means that running Flash on a mobile device can affect how long the battery lasts, whether the video is more like a slide show than a movie, and whether anything else can be happening in the background while you play a game. Jobs isn't about to let some other company's technology take the iPad's claimed 10-hour battery life down to five. And if the device sputters every time it shows a moving image, Apple's user experience — for which Apple can charge more than its competitors — gets put at risk. Adobe's Ludwig denies these are insurmountable technical problems, and he may have something there.

????Flash challenges Apple's business model

????Apple makes devices that consumers drool over — but they also have figured out how to get into people's pocketbooks in a way that businesses drool over. Apple's iPhone App store, and the iTunes store have been incredible successes (and Apple is counting on the same riches to come with the planned iBook store). If Flash were allowed on the iPhone or the iPad, software developers would have free rein to sell apps directly to consumers, bypassing Apple's shops and Apple's cut of the sale. If Flash were on the iPhone, you could watch Hulu and play games on Mini-Clip rather than buying movies from iTunes or buying games from the App store. (Adobe is also getting ready to launch a workaround that lets the 2 million or so Flash developers out there easily convert their applications for the iPhone, iPod and now iPad — but they will still be approved by and sold through Apple.) Flash breaks down the control Apple has over what gets on its devices and who gets paid for it. Which brings us to the porn theory.

????Flash opens up a market that Apple and its wireless partners don't want to enter

????The vast majority of porn is streamed using — you guessed it — Flash. Apple is keeping Flash out, this segment of theorists contend, because it doesn't want its devices to be the best porn products on the planet. Not to mention the network problems it might cause. It's bad enough with simple web-surfing to get your iPhone to work in San Francisco and New York, if everyone were watching streaming skin flicks in HD, you can imagine that AT&T (T) would simply be unusable.

????Apple is developing its own competitor to Flash

????This one hasn't progressed past pure conjecture. But considering how much control it would give Apple in content, across the devices and across the Web, it seems possible. And control, to Apple, is always a good thing.

????Adobe is set to release Flash 10.1 some time this year, and pretty much every mobile device or mobile operating system maker, including Research in Motion (RIMM), Samsung, Palm (PALM), and Google (GOOG), is prepping their devices for the upgraded Flash. Very soon, practically every new smartphone on the planet, and all those iPad wannabes coming out, will run Flash. So technically, it seems, it's possible.

????The truth about why Apple seems to hate Adobe is probably a bit of the technical with a lot of the business model reason thrown in. Flash is not good for Apple's business, it pokes holes in the perfect ecosystem that Jobs and his team have built. When every other mobile device has Flash built in, will Apple be forced to make nice with Flash? Perhaps, but until then, you can expect Apple to keep ignoring Adobe.