Samsung Galaxy S3
A concept design photo of Samsung Galaxy S3. NAK Studio

The iPhone 4S, presently Apple's flagship smartphone, was released in October and remains one of the most high-profile in the market. The company is rumoured to be preparing for the launch of its successor, tagged the iPhone 5.

Meanwhile, Apple's fiercest rival in this field, Samsung, is apparently all set to launch the successor to its best-selling Galaxy S2, at an event scheduled for 3 May in London.

Check out how the two leading smartphones stack up

Display: A recent report suggests the official service manual of the GT-19300 (believed to be model number for the Galaxy S3) has been leaked and one of the specifications uncovered is the phone will have a 4.8-inch Super AMOLED display. The leaked report was noted by Sammobile. This runs contrary to an earlier rumour, on CNET UK, which said the S3 would feature a 4.6-inch display with a resolution of 720x1184 pixels. Meanwhile, the iPhone 4S features a 3.5-inch multi-touch Retina Display with a resolution of 640x960 pixels. The display features fingerprint-resistant oleophobic coating and supports multiple languages and characters.

Size: Samsung has not revealed any information on the dimensions. However, an earlier IBTimes UK report speculated the S3 could be both thinner and heavier than its predecessor. The S2's direct competitor, the iPhone 4S, measures 115.2 x 58.6 x 9.3mm and weighs 140g.

Operating System: The Galaxy S3 will run on Android 4.0 (Ice Cream Sandwich). The iPhone runs on Apple's proprietary iOS software - iOS 5.1.

Processor: Samsung recently confirmed its next Galaxy device would be powered by a 1.4GHz Exynos 4 quad-core processor. The Exynos 4 quad-core has twice the processing capabilities over the 45nm process-based Exynos 4 Dual and consumes 20 percent less power, according to Market Watch. The handset will house 1GB RAM. Apple's iPhone 4S is powered by the Apple A5 chip, with a dual-core 1GHz Cortex A9 processor and 512MB of RAM.

Camera: The Galaxy S3 is expected to have an eight megapixel front-facing camera with LED flash and the ability to capture video at 1080p. The iPhone 4S has an eight megapixel iSight camera with auto-focus, tap-to-focus, face detection and LED flash. The camera can capture HD videos in 1080p at up to 30 frames per second. The iPhone also features a secondary front-facing VGA-quality camera.

Connectivity: The Galaxy S3 could offer Wi-Fi 802.11 b/g/n and Bluetooth version 4.0 and the handset will also support data speed up to HSPA+21Mbps and HSUPA 5.76Mbps. The Galaxy S3 is expected to feature a wireless charging technology. The iPhone 4S supports Wi-Fi 802.11 b/g/n and Bluetooth version 4.0.

Storage: The S3 is expected to come with internal memory of 16GB and support for a microSD card. The iPhone 4S comes with three options - 16/32/64GB but does not support for a microSD card.

Battery: The Galaxy S3 is expected to house a 3050mAh whereas the iPhone 4S is powered with a Li-ion battery.