No Flash on the iPhone? It's not a problem for advertisers, apparently. Developers tasked with creating rich media ad units for Apple's popular mobile devices have been busy porting their Flash-created ad collateral into an iPhone-friendly HTML5 format using mobile ad firm Greystripe's "iFlash" ad technology, which provides a Flash-like ad experience.

The iFlash ad format has become so popular, in fact, that Greystripe is just now announcing a 200% growth spike for these "iFlash" ads following the iAds announcement.

According to news the company linked to by way of Twitter post, but not press release, the growth for the 18-month old iFlash technology is due to the experience it offers, something that's similar to Apple's recently announced iAds technology. Like iAds, iFlash also provides rich media animation, touch interactivity and click-through actions, all of which are available without leaving the mobile application where the ad appears.

Greystripe's CEO Michael Chang sees iAds' imitation as a form of flattery in this case, proof that his company is doing it right. "Apple's selection of an ad format almost identical to our 'iFlash Custom' ads is a testament to the incredible potential of interactive, rich media mobile advertising and the value of customer engagement," he is quoted as saying.

The company claims it holds a 75% market share on the full screen rich media mobile market and have ads that reach 14 million unique monthly users in the U.S. Over the past two years, it has served over 2 billion full screen rich media impressions. Recent reports from comScore Inc. put the CTR for these iFlash ads at 2-5% on average, with 15-30+ seconds of user engagement.

While "fat-fingering" may contribute to some accidental ad launches, it's the engagement time that's really telling. Spending half a minute watching or interactivity with an ad is proof that creative, engaging ads can and do appeal to mobile users. (At least for now. Web banner ads used to be popular too, believe it or not).

Flash's Backdoor to iPhone

What's interesting about this news, besides, of course, the incredible growth rates the company is seeing, is how the iFlash ad technology actually works. It takes pre-created rich media ad units that were built using Adobe Flash and transcodes them to run on the iPhone, iPod Touch and, as of this month, iPad. The resulting ads are transformed into HTML5 format, a web standard that is supported on Apple's iPhone operating system.

For ad developers used to working with Flash technology, iFlash is essentially a workaround for the Flash ban on Apple devices, explained in detail by Steve Jobs himself back in April.

Apple caused quite a stir when it announced that iPhone apps created using Adobe's now-discontinued Packager for iPhone would not be allowed into the iTunes App Store, prompting Jobs' eventual response to all the hubbub. The Adobe software had allowed developers to create mobile applications using Flash and then port those to an iPhone-ready format. Although the technologies behind the Adobe converter and the iFlash transcoder are quite different on the back-end, the idea is the same: create with Flash, then port to iPhone.

With Apple's iAds launch just around the corner, one wonders if Apple will continue to allow a Flash transcoding product that competes directly with their own advertising initiatives to remain in business. Booting them out, though, would be tricky. After all, iFlash ads are in supported HTML5 format. Still, considering Jobs' opinions on Flash, it must irk him to see that Flash developers have found such an easy workaround for the Flash ban, if not for apps, at least for ads.