With a number of great devices readily available from leading manufacturers like Samsung, Apple and Motorola, the so-called smartphone war has never been so intense and fierce.

Announced on Oct. 4, Apple's iPhone 4S will be launched on Oct. 14, while Samsung launched its Galaxy S2 in the U.S. sometime in the middle of last month. Below is a comparison of the two rivals, based on their specs, features and price.

Power: While the Samsung Galaxy S2 is powered by a dual-core 1.2GHz ARM Cortex-A9 processor, Mali-400MP GPU and Exynos chipset, the iPhone 4S features a 1GHz dual-core ARM Cortex-A9 processor, PowerVR SGX543MP2 GPU and an Apple A5 chipset.

Camera: The Samsung Galaxy S2 features an 8 megapixel camera with 3264×2448 pixels, autofocus and single LED flash and a 2 megapixel camera in front for video calling. Similarly, the iPhone 4S also comes with an 8 megapixel camera with 3264×2448 pixels, autofocus and LED flash. However, it only features a VGA front-facing camera. The cameras of both phones can shoot HD videos of up to 1080p.

OS: The Samsung Galaxy S2 runs on Android's 2.3.4 Gingerbread OS, while the iPhone 4S is loaded with the Apple's newest operating system - the iOS 5. It is a free software update bringing over 200 new features to the iPhone, the iPad and the iPod touch, including a location-aware reminders app, Newsstand, wireless syncing, Twitter integration, iMessage, a notification bar and widgets.

Display: The Samsung Galaxy S2 sports a 4.3-inch (4.52 for the Sprint Epic 4G Touch and T-Mobile USA's Galaxy S2) Super AMOLED screen with 800x480 screen resolutions. On the other hand, the iPhone 4S is coming with a 3.5-inch TFT Retina multi-touch display, with 960 x 640 resolutions at 330 ppi pixel density.

Storage on Board: The Galaxy S2 boasts 16GB of internal storage, which can be expanded up to 32GB via a microSD card. The phone has 1GB RAM. The iPhone 4S comes in 16GB, 32GB and 64GB models. It doesn't support a MicroSD card slot. Apple has not revealed the RAM of the iPhone 4S. However, reports claim that it has 512MB of RAM, similar to the iPhone 4.

Download Speed: With High-Speed Download Packet Access (HSDPA) technology, the iPhone 4S is claimed to have data download speed that is nearly twice as fast as the iPhone 4 - 14.4Mbps compared with 7.2Mbps. It supports 5.8Mbps of upload speed. The Samsung Galaxy S2 is an HSPA+ ready phone with 21Mbps download speed and 5.76Mbps upload.

Battery Life: Weighing 140g, the iPhone 4S has a Li-Po 1,420 mAh battery, which offers up to 8 hours of talk time on 3G networks and up to 14 hours on 2G (GSM). On the other hand, the Galaxy S2 features a Li-Ion 1650 mAh battery with 9 hours talk time and up to 576 hours stand-by time on 3G. It weighs 116g.

Price: The iPhone 4S costs $199 for the 16GB model, $299 for the 32GB model and $399 for the 64GB model. On Sprint, the Epic 4G Touch will cost $199.99 with a two-year contract. The AT&T version is expected to be in the range of $250 to $300, while T-Mobile is yet to announce pricing or availability details.

Meanwhile, Apple received more than a million pre-orders for the iPhone 4S in a single day, which toppled the previous record of 600,000 set by the iPhone 4 last year, according to a statement by the company.

The pre-order numbers for the iPhone 4S put Apple on target to sell around 3 million in its first weekend, according to Mike Abramsky, of RBC Capital Markets, as reported by AppleInsider.

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