California-based tech giant, Apple Inc., received an overwhelming response from all around the world for the iPhone 4S. However, a host of Android-powered phones, sporting quad-core, 1.2GHz and 1.5GHz chipsets could spoil the Cupertino giant's party.

Apple unveiled the iPhone 4S, instead of the eagerly anticipated iPhone 5, on Oct. 4. As it turned out, the smartphone featured some important upgrades that were rumored to be a part of the imaginary iPhone 5, like the 1GHz dual-core ARM Cortex-A9 processor, PowerVR SGX543MP2 GPU, an Apple A5 chipset and an 8 megapixel LED flash camera with 1080p HD video recording capabilities.

In addition, despite retaining a 3.5-inch TFT Retina multi-touch display, the iPhone 4S is loaded with Apple's newest operating system - the iOS 5. It also comes with alternating antennae for better call reception, CDMA and GSM support, a personal assistant called Siri, iCloud and Bluetooth 4.0 wireless technology.

The pre-order sales, which started on Oct. 7, for Apple Inc.'s iPhone 4S has crossed one million units in a single day, breaking the previous record set by the iPhone 4 of 600,000 first day orders.

A slew of Android-run tablets, which are powered by dual-core 1GHz processors, were showcased at the 2011 Consumer Electronic Show (CES). Since then, phones like the Samsung Galaxy S2 and HTC Sensation, which run on dual-core 1.2GHz processors have upped the ante for the iPhone 4S.

Furthermore, rumors suggest there are even a few Android phones rocking quad-core chipsets that are on the anvil. NVIDIA recently announced the launch of its Kal-El Tegra 3 line of quad-core processors, while Qualcomm is working on Krait architecture-based chips that are expected to run at speeds of up to 2.5GHz. Qualcomm's quad-core chipset will be released under the moniker APQ8064.

According to a AnandTech report, it is expected that NVIDIA's quad-core chips will become official by the end of the year. Qualcomm's Krait will debut in three configurations: a single-core MSM8930, dual-core MSM8960 and quad-core APQ8064. Both the single-core MSM8930 and the quad-core APQ8064 should be available for sampling in early 2012.

Here are some rumored Android-powered phones which pack in ultra-fast processors that could compel Apple to change its processor strategy for iPhone 5, which analysts are expecting to launch in 2012.

Samsung Celox

A Galaxy S2 lookalike, the Samsung Celox, appeared in Korea early in August. It is rumored to have a 4.5-inch Super AMOLED screen with 800x480 screen resolution and will be powered by a 1.5GHz dual-core Qualcomm Snapdragon APQ8060 chipset.

The Celox will also support two cameras - an 8 megapixel camera at the rear and a 2 megapixel camera in the front. It is also being reported that the Celox will sport a 1750 Li-ion battery. The Celox is a tad thicker and heavier than perhaps ideal, weighing 4.5 ounces and being 0.36 inches thick. The Celox runs on Android Gingerbread juice.

HTC Holiday

Rumored pictures of the HTC Holiday were released by an XDA Developer forum member. It is speculated that the Holiday will feature a 4.5-inch capacitive screen with 960x540 screen resolution and will be powered by a 1.2GHz dual-core Qualcomm MSM8660 processor. It will offer 1GB RAM and will sport an 8 megapixel camera. The Holiday is surmised to also run on Android Gingerbread juice. The phone is slated to be released on AT&T's network.

Nexus Prime

The launch of the Nexus Prime, the latest smartphone based on Google Inc.'s new version of the Android operating system - Ice Cream Sandwich, has reportedly been delayed, out of respect for the recent death of Apple's co-founder Steve Jobs, who passed away on Oct. 5.

Samsung, whose phone the Nexus Prime is, will reportedly power the device with either a Qualcomm Snapdragon Krait chipset or Texas Instruments' OMAP4460 chipset clocking at 1.5GHz. The Nexus Prime is expected to have a dual-core 1.2GHz or 1.5GHz processor. The phone is rumored to have a monster-sized display, 1GB RAM, a 5 megapixel rear-facing camera with 1080p video capture capability and will come sans physical buttons.

Motorola

In April, rumors abounded that Motorola would be the first company to offer quad-core devices. The two devices in the limelight were the Motorola Bullet and the Jet. Both phones are rumored to be powered by NVIDIA's quad-core Tegra 3 (Kal-El) processor.

The Bullet is expected to feature a 4.3-inch qHD screen, 1.5GB RAM, 16GB internal memory, a Near Field Communication (NFC) chip and a 12 megapixel camera with a fully re-designed sensor. The Jet, on the other hand, is expected to feature similar specifications on a smaller 4-inch display. It is also expected to feature a QWERTY keyboard.

Pantech

Korean phone-maker Pantech released an Android phone called Vega Racer in Korea. The phone features a 1.5GHz dual-core Qualcomm MSM8660 processor. It offers 1GB RAM, a 4.3-inch LCD display with 800x480 screen resolution, an 8 megapixel rear-facing and a 1.3 megapixel front-facing cameras. The phone weighs a mere 4.23oz and is 0.35-inches thick.

Samsung GT-i9220

The GT-i9220 from Samsung is rumored to be a complete departure from the traditional 4.3 and 4.5-inch form factor. Instead, it is believed to feature a 5.3-inch display. The GT-i9220 is also expected to arrive with the first HD-ready screen that will use Samsung's Super AMOLED Plus HD technology at 1280x720 pixels.

It is rumored that the phone will feature a dual-core 1.4GHz CPU, which may possibly be a Samsung Exynos model. An 8 megapixel rear camera and a front facing camera, whose specifications are part of the design yet to be revealed, will also be available. The device will run on Android Gingerbread juice and offers 16GB of onboard storage with 1GB RAM.

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