The first generation iPhone was Apple’s first handheld device that combined mobile phone, iPod and internet into one platform. These GSM Quad-band phones operate on 850, 900, 1800 and 1900 MHz frequencies and sport a 3.5” display with 320x480 resolution at 163ppi. The first generation iPhones where available in 4GB, 8GB or 16GB of configurations with 128MB standard RAM. Built in Wi-Fi 802.11b/g, EDGE and Bluetooth 2.0 provide multiple connectivity options. A 2.0 megapixel camera integrated into the 4 ounce .46” thick aluminum casing made this a highly demanded phone.
Apple initially estimated the Lithium Ion battery provided up to 16 hours of audio playback and up to 5 hours of talk, video, and browsing but on June 18, 2007, Apple increased those times to up to 8 hours talk time, 24 hours audio playback, 7 hours of video playback, and 6 hours web browsing. It also features up to 250 hours standby time. The multi-touch screen allows the user to control all functions with one or more fingers on the optical quality glass display. Also included is an accelerometor that enables the device to detect whether it is being held in portrait or landscape mode. An ambient light sensor adjusts the screens brightness according to lighting conditions and proximity sensor disables the display when the phone is held to the ear.
The iPhone 3G is similar to the first generation iPhone but is also able to connect to the 3G (850, 1900, 2100 MHz 3.6 Mbps) network and is GPS enabled. Apple used the same 3.5” display with 320x480 resolution at 163 ppi, but the new back consists of either a black or white plastic cover. This cover added 0.02 of an inch to the entire phone. 8GB or 16GB configurations are available with 128MB onboard RAM.
The Lithium Ion battery provides up to 24 hours audio playback, 10 hours talk time on 2G, 5 hours talk time on 3G, 5 hours internet use on 3G, 6 hours internet use on Wi-Fi, 7 hours video playback and 300 hours standby time.
From the exterior, the iPhone 3GS appears to be identical to the iPhone 3G. However the 3GS has a number of internal modifications. The 3GS uses a 600MHz processor rather than 412MHz and an improved graphics processor. RAM has been increased to 256MB from 128MB and supports the faster 7.2 Mbps HSDPA network. It sports 3.0 megapixel camera that supports autofocus, macro, white balance and VGA video recording at 30 fps is now standard. Videos can also be trimmed. 16GB and 32GB models are available which provide up to 30 hours of audio playback, 12 hours talk time on 2G, 5 hours talk time on 3G, 5 hours internet on 3G, 9 hours internet on Wi-Fi, 7 hours video playback and 300 hours standby time.
The iPhone 4 is the best phone ever to hit the market and has been completely redesigned from the previous 3GS. The heart of the iPhone 4 is the new A4 chip first featured in the iPad. This high-speed processor allows for multitasking and video calls, while maximizing battery life. Ram has increased to 512MB from 256MB. New Wi-Fi chip allows for faster 802.11b/g/n Wi-Fi capability. Battery life has increased to 7 hours of talk time on 3G and 14 hours on 2G, 6 hours of internet use on 3G and up to 10 hours on Wi-Fi, 10 hours of video playback, 40 hours of audio playback, and 300 hours of standby time. The retina display features more pixel density then the human eye can distinguish with 960 x 640 pixel resolution at 326 ppi. The glass that covers this gorgeous screen and back cover is made from aluminosilicate glass, which is also used in high-speed trains and helicopters. The glass and internals are held together by a stainless steel band forged to be five times the strength of standard stainless steel making the iPhone 4 ultra-rigid and incredibly thin. The iPhone 4 supports 720p video playback at 30 frames per second. The new camera on iPhone 4 is 5-megapixel and features a LED flash that works for both photos and video. Video is recorded in stunning 720p high-definition clarity. The front camera on the iPhone 4 is used for video calls, or FaceTime, as Apple has dubbed it. The new iPhone 4 is the only phone that can take advantage of the FaceTime calls. Also, a new gyroscope censor allows for advanced motion sensing on three-axis to allow for an unbelievable gaming experience. There are two microphones, with the second mic working to suppress unwanted background noise. All these features are packed into the iPhone 4's 9.3mm thin casing, 24% thinner than the previous 3GS.