Apple’s iPad will continue to reign the swelling tablet market this year even though it already has several competitors from various computer and mobile-device companies, according to a report released by research firm Gartner.

Gartner said iPad, which is synonymous to the term “tablet,” sets the standards for what the device really is, thus, leaving a small room for alternatives.

The firm expects 70 million tablets to be sold within this year and about 108 million in 2012. The expected number is way beyond the 17.6 million tablet sales in 2011.

Google trails behind Apple in the second position. The firm said Google’s Android operating system is still insufficient to match up with Apple.

However, Gartner said Google’s shares will rise to 39 percent in 2015 from 20 percent this year while Apple’s shares will gradually drop to 47 percent from 69 percent.

Research in Motion’s Playbook tablet, which uses the new QNX platform, gets the third spot in the market this year with a 5.6 percent market shares, which Gartner believes will rise to 10 percent in 2015.

The firm said time and remarkable effort is required for RIM to obtain more customers and developers that will deliver a more innovative group of services and applications around QNX. Carolina Milanesi, Gartner analyst said this method will make a feasible alternative to Android or Apple.

Milanesi said organizations that will be interested in RIM’s new QNX-run tablet will consist of those who have RIM’s infrastructurre or those who have strict security requirements.

Amazon.com officially opened its Android Appstore on Tuesday. The store offers thousands of free and paid software applications for tablet computers and smartphones running Google’s Android operating system.

However, Apple Inc issued a trademark complaint against the largest online retailer in United States. Apple decided that the name of Amazon’s online application store is just too similar with their App Store.

The Amazon Appstore offers features that challenge Google’s own Android Market. It allows users to test applications that they are interested with a simulated Android phone. The simulated phone can be accessed through the computer using a mouse. Amazon calls it the “Test Drive.”

The company, in collaboration with Rovio Mobile, also offers another perk to its users through their Appstore. The Angry Birds Rio for Android will be launched exclusively at their Appstore. This allows customers to download the app for free, but only for a limited time. Amazon will also launch ad-free versions exclusively for Angry Birds and Angry Birds Seasons.

In 2008, Apple made an application to register the name “App Store” as a trademark in the United States. It has even attracted legal challenge from Microsoft Inc. Today, the application is still under consideration at the Patent and Trademark Office.

Apple wanted Amazon to stop using the name. It said consumers might be confused whether Amazon’s application store is approved or sponsored by Apple.

Amazon software developers will get 70 percent of the sales. However, the company will set the prices for each application. There are about 3,800 applications available in the site now. It can be downloaded through a mobile app or through the web interface.

Currently, Amazon Appstore is only available in the United States.