One of the more infamous decisions that Apple has made of late is excluding Adobe Flash support from their iPhone and iPad, along with banning conversions of Flash-to-iPhone. Today, Apple CEO Steve Jobs posted an open letter detailing why his company does not allow Flash on his company’s portable devices, and he claims it is a decision based on technology, not on protecting the company’s App Store.

He notes that Adobe’s Flash is not an open system, unlike HTML 5 which is used by Apple, Google and others. Jobs also said that using the video format H.264, users are able to access most videos on the web. He also detailed that Flash has reliability and performance issues (citing it as the top reason Macs computers crash) and isn’t suited to battery operated devices.

“Although Flash has recently added support for H.264, the video on almost all Flash websites currently requires an older generation decoder that is not implemented in mobile chips and must be run in software,” wrote Jobs.  “The difference is striking: on an iPhone, for example, H.264 videos play for up to 10 hours, while videos decoded in software play for less than 5 hours before the battery is fully drained.”

The most important reason for the lack of Flash support, Jobs argues, stem from relying on cross-platform third-party software for development, because of quality issues. “Our motivation is simple we want to provide the most advanced and innovative platform to our developers, and we want them to stand directly on the shoulders of this platform and create the best apps the world has ever seen,” writes Jobs. “We want to continually enhance the platform so developers can create even more amazing, powerful, fun and useful applications. Everyone wins we sell more devices because we have the best apps, developers reach a wider and wider audience and customer base, and users are continually delighted by the best and broadest selection of apps on any platform.”

“Flash was created during the PC era for PCs and mice. Flash is a successful business for Adobe, and we can understand why they want to push it beyond PCs. But the mobile era is about low power devices, touch interfaces and open web standards all areas where Flash falls short. The avalanche of media outlets offering their content for Apple’s mobile devices demonstrates that Flash is no longer necessary to watch video or consume any kind of web content. And the 200,000 apps on Apple s App Store proves that Flash isn t necessary for tens of thousands of developers to create graphically rich applications, including games. New open standards created in the mobile era, such as HTML5, will win on mobile devices (and PCs too). Perhaps Adobe should focus more on creating great HTML5 tools for the future, and less on criticizing Apple for leaving the past behind,” concluded Jobs.