Preliminary benchmarks of the iPhone 4S that surfaced on the Internet have been found to show that the A5 processor in the iPhone 4S performs at about 75 percent of the capability of the 1GHz A5 processor in the iPad 2. This would peg the A5 processor in the iPhone 4S at 800MHz, according to Anandtech. However, its real-world scripting, browser and graphics performance currently puts it well ahead of its main Android competition, in the Samsung Galaxy S II and the Motorola Droid Bionic.
Despite running at a clock speed below its Android Gingerbread competition, and using apparently only half the RAM, the A5 processor in the iPhone 4S is able to outperform the Samsung Galaxy S II with its dual-core 1.2GHz Exynos processor and the Motorola Droid Bionic with its dual core 1.2GHz TI OMAP processor because of the way that Gingerbread ultilizes processors when browsing.
Where Android 3.0 (Honeycomb) and Android 4.0 (Ice Cream Sandwich) are capable of addressing both processor cores when browsing, Gingerbread only addresses one of the two cores. If, and when, the Galaxy S II and the Droid Bionic get an update to Ice Cream Sandwich, their performance in Javascript is expected to increase markedly.
However, the graphics performance of the iPhone 4S will continue to outshine both the Galaxy S II and the Droid Bionic, despite its lower clock speed. The dual-core Power VR SGX 543 processor found in the A5 processor has a significant edge in performance over the Mali 400 GPU found in the Samsung Exynos 1.2GHz processor found in the Galaxy S II and the single core SGX 540 found in the TI OMAP 1GHz processor in the Droid Bionic that will not change with an OS update.
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