Design (left) made of aluminum and plastic, and the iPhone 3G (right) made entirely from a hard plastic material The iPhone 3G's back featured a redesigned plastic housing, replacing the aluminum back of the first generation. The housing is made of clear
polycarbonate painted either black or white on the inside. Buttons were changed from plastic to metal, and the edges of the phone were tapered, providing a better grip. The iPhone 3G introduced the first official color options for the outer casing, with the 16 GB version available in black and white. The dimensions of the iPhone 3G were marginally larger than those of the original iPhone. It was high, wide, and deep, compared to its predecessor, which was high, wide, and deep. The iPhone 3G sported a capacitive touchscreen with a 480×320 (
HVGA) resolution at 163
ppi. The scratch-resistant glass sits on top of the display. Just like the original iPhone, the touchscreen was designed for a bare finger, or multiple fingers for multi-touch sensing. The device featured the same sensors as its predecessor. The proximity sensor (which deactivates the display during calls when the face is near) was repositioned to save battery power and to prevent inadvertent inputs from the user's face and ears. An ambient light sensor was included to adjust the display brightness for different lighting conditions, which helps save battery power. A 3-axis
accelerometer was included to sense the orientation of the phone and change the screen accordingly, allowing the user to easily switch between portrait and landscape mode.
Processor and memory Most of the iPhone 3G's internal hardware is based on the original
iPhone. It includes a
Samsung 32-bit
RISC ARM11 620 MHz processor (underclocked to 412 MHz), a
PowerVR MBX Lite 3D
GPU, and 128 MB of
package on package (PoP)
DRAM, as the original iPhone did.
Rear camera On the rear of the device, the iPhone 3G features the same fixed-focus 2.0
megapixel camera of its predecessor. This camera does not have optical zoom, flash, autofocus, or native video recording, although various applications became available to allow video recording on the device. The iPhone 3G's operating system supports the
geotagging of photographs.
Connectivity In addition to
EDGE, the iPhone 3G supports
Assisted GPS,
3G data, and
tri-band UMTS/
HSDPA. These enhancements allow faster data downloads and
turn-by-turn navigation with maps compared to previous devices. Like its predecessor, the iPhone 3G features a proprietary 30-pin dock connector for charging the device. It can also be used to synchronize the device with a computer and to connect various accessories. The iPhone 3G features a flush-mounted 3.5 mm headphone jack instead of the recessed headphone jack that was included on the original iPhone; it could, therefore, be used with any headphones other than those provided by Apple.
Battery The iPhone 3G features an internal rechargeable battery rated at 1150 mAh, which, like its predecessor, is not user-replaceable. Apple stated that the iPhone 3G's battery is capable of providing up to six hours of web browsing via
Wi-Fi, or five hours via 3G, or 25 hours of audio playback. Alternatively, it is said to provide 300 hours of standby time. == Reception ==