Apple’s iPad will continue to account for the majority of the global media tablet market through 2015, according to a new report from Gartner.

Because of the popularity of Apple’s iPad, iOS will account for 69 percent of media tablet OSs in 2011, and represent 47 percent of the media tablet market in 2015.

“Seeing the response from both consumers and enterprises to the iPad, many vendors are trying to compete by first delivering on hardware and then trying to leverage the platform ecosystem,” said Carolina Milanesi, research vice president at Gartner.

“Many, however, are making the same mistake that was made in the first response wave to the iPhone, as they are prioritizing hardware features over applications, services and overall user experience. Tablets will be much more dependent on the latter than smartphones have been, and the sooner vendors realize that the better chance they have to compete head-to-head with Apple.”

Google’s Android OS is on track to increase its global share of the media tablet market from 20 percent in 2011 to 39 percent in 2015. Analysts said Google’s decision not to open up the Honeycomb, its first OS version dedicated to tablets, to third parties will prevent fragmentation, but it will also slow the price decline and ultimately cap market share.

“Volume will be driven by support from many players, the ecosystem of applications for tablets getting more competitive and some platform flexibility allowing lower price points,” said Roberta Cozza, principal analyst at Gartner.

“The new licensing model Google has introduced with Honeycomb enables Google to drive more control, allowing only optimal tablet implementations that don’t compromise quality of experience. This might mean that prices will drop at a slower pace than what we have seen in the smartphone market.”

Research in Motion’s QNX OS, used on the forthcoming BlackBerry Playbook tablet, will offer users a consistent expereince across its entire prorduct portfolio and create single developer community.

It will take time and significant effort for RIM to attract developers and deliver a compelling ecosystem of applications and services around QNX to position it as a viable alternative to Apple or Android. This will limit RIM’s market share growth over the forecast period,” Ms. Milanesi said.

“It will be mainly organizations that will be interested in RIM’s tablets because they either already have RIM’s infrastructure deployed or have stringent security requirements.”

Gartner analysts said platforms such as MeeGo and WebOS, which currently have a weak presence in the smartphone market, will have a limited appeal unless they can grow that business.

“Smartphone users will want to buy a tablet that runs the same operating system as their smartphone. This is so that they can share applications across devices as well as for the sense of familiarity the user interfaces will bring,” Ms. Milanesi said.

“Vendors developing on Android should be prepared to see more cross brand ownership as some users might put OS over brand when it comes to the purchasing decision. Improvements on usability and brand recognition are the strongest differentiators they can focus on.”