As of December 2013, one out of five tablet computers that were sold around the world is an iPad, meaning the iPad Air, the iPad Mini with Retina and previous versions of the iOS slate from Apple.

According to Apple Insider, 20 per cent of the tablet computers that cleared retail stores on known markets last year are iPads. And basing on the new forecast issued by NPD DisplaySearch, the trend will only continue.

Over the next four years, total shipment in the mobile computing market is expected to shoot up to 450 million units and 75 per cent of which are tablets. Researchers are projecting that the upcoming generations of today's iPads will continue to dominate the competition.

"Momentum for the tablet PC market is in full swing as they have become the dominant mobile PC form factor," NPD analyst Richard Shim was reported by Apple Insider as saying.

The NPD report also suggested that the current crop of tablet players aside from Apple - Samsung, LG, Asus and Amazon - will become crowded as traditional PC makers like Lenovo, HP and Dell will begin the gradual transition from desktops and laptops to the more portable tablet computers.

Predicting that the iPad Air and iPad Mini will remain on top of the tablet food chain is almost automatic as a strong challenger against Apple is yet to emerge.

Google's Nexus tablets, while considered as the toughest iPad rivals out there, appear struggling to find the right formula that will make the Nexus 7 and Nexus (or even the rumoured Nexus 8) worthy of tussling with the iOS slates.

To date, the 7-inch Nexus 7s (builds 2012 and 2013) have yet to match the huge popularity of the iPad Mini. Same goes for the Nexus 10 2, which has been long-rumoured to give a better fight to the slimmed down and lighter (but more powerful) iPad Air.

Until now, the supposed Nexus 10 replacement, made by Samsung, is nowhere to be found.

Even Samsung's own line of Galaxy tabs, while enjoying considerable amount of commercial success, are considered inferior to the iPad duo when sales figures is the basis of the competition.

So, as gleaned in the NPD report, the iPad will stay on top of its game as the global PC market continues to shift from the conventional form to mobile computing.

There is no clear hint for now on what the 2014 builds have in store for Apple fans but it is highly likely many of the features recently attributed to the rumoured iPhone 6 will also be packed with the refreshed iPad Air and Retina iPad Mini.

Among the features that possibly will amaze come the 2014 iPad Air and iPad Mini release date are the following: Liquidmetal casing for tougher tablet shell, sapphire glass and coating for extra durability, TouchID fingerprint scanner that was absent in the 2014 versions and a new iOS, which could be 7.2 or iOS 8.