Given the likelihood one of the biggest rivals of the iPhone 4S will be the Samsung Galaxy S2, it will be interesting to have a comparison of the features of the two competitors.

The Galaxy S2 is 8.49mm thick and it weighs just 116g. The iPhone 4S is not as thin as the Galaxy S2, measuring 9.3mm; it is a shade heavier, too, at 140g.

The Galaxy S2 runs on the Android 2.3 Gingerbread OS. Although the Android OS is capable of giving a user a very considerable amount of computing power, the fact the Android apps market is cluttered with so many applications can make navigating it an annoying process. Meanwhile, the iPhone 4S, equipped with the recently announced iOs 5, is touted as being very simple to use. The apps are arranged in grids of 12 across multiple screens, making navigation a potentially easier task.

The Galaxy S2 packs an 8-megapixel camera with a single LED flash that is capable of capturing 1080p video footage; something which the iPhone 4 did not have. However, its upgrade -- the 4S -- has matched the Galaxy's specs in this department, with an 8-megapixel camera capable of capturing 1080p video footage.

The Samsung Galaxy S2 has a 4.3-inch, 800x480-pixel screen that incorporates Super AMOLED Plus technology. The iPhone 4S has a marginally smaller screen -- at 3.5 inches -- but boasts a Retina display of 960x640-pixel resolution at 326 ppi.

On the one hand, the iPhone 4S is powered by a dual-core A5 chip, which also has dual-core graphics capabilities. On the other hand, the Galaxy S2 has a 1.2GHz dual-core Qualcomm processor. The phones are believed to be well-matched in this department.

Customers can now preorder the 4S (the preordering process started Friday). The phone itself will be available Oct. 14 in the U.S., Canada, Australia, the United Kingdom, France, Germany, and Japan.

The next few months should see the competition between the 4S and the S2 heat up!

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