In an evident attempt to intensify its competition with Apple, prior to this year's holiday season, online retail giant Amazon unveiled four new Kindle Fire models at a September 6 event.

The new models unveiled by Amazon on Thursday comprise notably more powerful versions of the company's existing Kindle Fire tablet; and included one model which is almost the same size - but much more affordable - as the Apple iPad.

Interestingly, while Apple is being rumored to come up with a smaller iPad, the four new Kindle Fire tablets which were introduced by Amazon included two bigger screen models - a 7-inch Kindle Fire HD; and an 8.9-inch Kindle Fire HD - which will boast high-resolution displays, two-fold more storage than the existing model, and stereo speakers with Dolby Labs' audio-processing software.

While the 7-inch Kindle Fire model - the shipments of which will commence on September 14 - will be priced at $199; the 8.9-inch version, which will hit the stores on November 20, will cost in the range of between $299 and $599.

Other than these two larger-screen models, the new Kindle Fire version that Amazon introduced at the event included a premium 4G-capable Kindle Fire model which will feature a 22.6cm screen and 32GB of memory; and an enhanced version of the original Kindle Fire which would cost $159, and will boast a speedier processor, a bigger battery, and more storage capacity.