The iPhone 4 is a smartphone that was developed and marketed by Apple. It is the fourth generation of the iPhone lineup, succeeding the iPhone 3GS and preceding the iPhone 4s. Following a number of notable leaks, the iPhone 4 was first unveiled on June 7, 2010, at Apple's Worldwide Developers Conference in San Francisco, and was released on June 24, 2010, in the United States, United Kingdom, France, Germany, and Japan.
The iPhone 4 introduced a new hardware design to the iPhone family, which Apple's CEO Steve Jobs touted as the thinnest smartphone in the world at the time; it consisted of a stainless steel frame that doubled as an antenna, with internal components situated between two panels of aluminosilicate glass. The iPhone 4 introduced Apple's new high-resolution "Retina display" (with a pixel density of 326 pixels per inch) while maintaining the same physical size and aspect ratio as its predecessors, Apple's A4 system-on-chip, and with iOS 4—which notably introduced multitasking functionality and app folders. It was the first iPhone at the time to include a front-facing camera, which made possible Apple's new FaceTime video chat service, and the first to be released in a version for CDMA networks, ending AT&T's period as the exclusive carrier of iPhone products in the United States.
The iPhone 4 received a largely positive reception, with critics praising its revamped design and more powerful hardware, in comparison to previous models. While it was a market success (with over 600,000 pre-orders within 24 hours), the release of the iPhone 4 was plagued by highly publicized reports concerning abnormalities in its new antenna design that caused the device to lose its cellular signal if held in a certain way. Most direct contact with the phone's outer edge would cause a significant decrease in signal strength. Apple released iOS 4.0.1 to try to fix these issues, but were unsuccessful.
The iPhone 4 spent the longest time as Apple's flagship iPhone model at fifteen months. Although the succeeding 4S was announced in October 2011, the 4 continued to be sold as a midrange model until September 2012, and thereafter as the entry-level offering in Apple's lineup until September 2013 with the announcement of the iPhone 5s and iPhone 5c. The iPhone 4 had one of the longest lifespans of any iPhone ever produced, spanning close to four years and available in some developing countries until early 2015.
History
Prototypes
Before the official unveiling of the iPhone 4 on June 7, 2010, two prototypes were brought to the attention of the media, breaching Apple's normally secretive development process. Many of the speculations regarding technical specifications proved accurate.
Engadget leak On January 27, 2010, gadget website Engadget received leaked images of the unreleased first-generation iPad. Unbeknownst to the editors and readers, these images contained two unreleased iPhone 4 models. It was not until the subsequent Gizmodo release that they were aware of the complete contents of the images.
Gizmodo leak On April 19, 2010, gadget website Gizmodo reported that they had purchased an iPhone prototype for $5000, and furthermore, had conducted a product teardown of the device. The prototype was reported to have been lost by an Apple employee, Gray Powell, in Redwood City, California. Shortly after Gizmodo published detailed information about the prototype, Apple's legal associates formally requested for the phone to be returned to Apple, and Gizmodo responded with the intent to cooperate.
On April 23, officers from the Rapid Enforcement Allied Computer Team (REACT) task force of the California HTTAP Program raided the home of Jason Chen, the Gizmodo editor responsible for reviewing the prototype, seizing all of his computers and hard drives. The Electronic Frontier Foundation criticized the raid as violating journalist source protection laws that forbid the seizure of journalist computers, as well as the suspicion that Apple had used its influence as a member of the steering committee, which is charged with direction and oversight of the California REACT task force to push police into action in a way that would not normally be conducted for this type of incident. Apple had already received the iPhone prototype before the raid when it was returned by Gizmodo. The District Attorney stated that the investigation was suspended, and discontinued searching through the Gizmodo editor's belongings as they determine whether the shield laws are applicable, and cautioned that no charges have been issued at this point.
Taoviet leak Pictures and video of a second prototype were published on a Vietnamese website, Taoviet, on May 12, 2010. It was almost identical to the first, and used an A4 chip manufactured by Apple. The website purchased the prototype for $4,000. DigiTimes reported that the screen resolution of the new phone was 960-by-640, which was confirmed by Apple at the iPhone 4's official announcement.
Release
The iPhone 4 was available for pre-order on June 15, 2010. Customers attempting to pre-order the iPhone 4 reported problems with the pre-order process on the US and UK online Apple Stores, which crashed due to the surge in traffic. The same issue was reported with AT&T and SoftBank, Apple's exclusive partners in the United States and Japan respectively, who suspended advance sales of the iPhone 4 as demand threatened to exceed supply. Retail stores were also unable to complete pre-order transactions due to the servers crashing.
Apple and its partner carriers received 600,000 pre-orders for the iPhone 4 in the first 24 hours, the largest number of pre-orders Apple had received in a single day for any device up to that point. Engadget reported that at 20:30 UTC, all iPhone 4 pre-order suppliers had sold out. 1.7 million iPhone 4 models were sold in its first three days of availability.
The iPhone 4 was also released through Orange in Tunisia and was available in eight cities at the launch. On July 30, 2010, iPhone 4 was made available for sale in Australia, New Zealand and 15 other countries with free bumper cases. In South Korea, it was released by KT on September 10. In Israel, it was released, too, on September 24, through Cellcom, Pelephone and Orange. It was launched in Thailand on September 23 by AIS, DTAC and True Move, and in Malaysia on September 26 in Kuala Lumpur, and nationwide on September 27 according to the Malaysian service provider Maxis.
The iPhone 4 was released in South Africa on September 22 on the Vodacom and MTN networks, in very limited quantities. The iPhone 4 was launched in Vietnam on September 30 on VinaPhone and Viettel, at first in three major cities: Hanoi, Ho Chi Minh City and Da Nang, and then all over the country by the end of October.
The iPhone 4 was launched in India on May 27, 2011, by Aircel and Airtel.
On January 11, 2011, Verizon Wireless announced during a media event that it had reached an agreement with Apple and would begin selling a CDMA iPhone 4 in the United States, ending Apple's exclusivity agreement with AT&T. The Verizon iPhone went on sale on February 10 and pre orders began on February 3. The Verizon iPhone includes the 'Personal Hotspot" feature that allows a user to use the iPhone as a wireless hotspot, with up to five devices connecting at one time. The February 3, 2011, presale of the iPhone 4 broke Verizon's first day sales records for a single device.
On June 24, 2010, Apple stated that the white iPhone 4 models were proving more "challenging to manufacture" than expected, and initially pushed the release date back to the second half of July. There was a lot of speculation surrounding the delay of the white iPhone 4. Among the most popular rumours are those concerning the phone's internal camera being adversely affected by light leaking in due to the semi-translucent glass and the white paint. Other sources report that the problem relates to Apple's inability to match the white color of the front faceplate with that of the home button. On April 27, 2011, Apple announced that it would be releasing the white iPhone 4 model on April 28, 2011, for both GSM and CDMA. The release of the white iPhone 4 was carried out on April 28.
During Apple's official unveiling of the iPhone 4s on October 4, 2011, it was announced that Sprint would begin carrying the CDMA iPhone 4 and the iPhone 4s in the US on October 14.
Discontinuation In September 2013, after the release of the iPhone 5s and iPhone 5c, Apple stopped selling the iPhone 4 in most of their stores as well as on their website. It was replaced by the 8 GB iPhone 4s.
Hardware
Display
The display of the iPhone 4 was manufactured by LG under an exclusive contract with Apple. It features an LED backlit TFT LCD capacitive touchscreen with a pixel density of 326 pixels per inch (ppi) on a (diagonally measured), 960×640 display. Each pixel is 78 micrometers in width. The display has a contrast ratio of 800:1. The screen was marketed by Apple as the "Retina display", based on the assertion that a display of approximately 300 ppi at a distance of from one's eye, or 57 arcseconds per pixel, is the maximum amount of detail that the human retina can perceive. With the iPhone expected to be used at a distance of about 12 inches from the eyes, a higher resolution would allegedly have no effect on the image's apparent quality as the maximum potential of the human eye has already been met.
This claim was widely disputed. Raymond Soneira, president of DisplayMate Technologies, said in an interview with the Wired magazine, that his claims by Jobs are something of an exaggeration: "It is reasonably close to being a perfect display, but Steve pushed it a little too far". Soneira stated that the resolution of the human retina is higher than claimed by Apple, working out to 477 ppi at from the eyes, or 36 arcseconds per pixel.
However, Phil Plait, author of Bad Astronomy, whose career includes a collaboration with NASA regarding the camera on the Hubble Space Telescope, responded to the criticism by stating that "if you have [better than 20/20] eyesight, then at one foot away the iPhone 4's pixels are resolved. The picture will look pixellated. If you have average eyesight, the picture will look just fine".
Camera
The iPhone 4 features an additional front-facing 640×480 camera, and a backside-illuminated 5 megapixel rear-facing camera with a 3.85 mm f/2.8 lens and an LED flash. The rear-facing 5-megapixel camera is capable of recording HD video in 720p at 30 frames per second. Both cameras make use of the tap to focus feature, part of iOS 4, for photo and video recording. The rear-facing camera has a 5× digital zoom.
Connectivity In contrast to Steve Jobs' announcement at WWDC 2010, Federal Communications Commission documentation showed that, in fact, the iPhone 4 contains a penta-band 3G UMTS antenna, not a quad-band 3G UMTS radio, as advertised by Apple. According to the FCC documentation filed by Apple, the radio inside the iPhone 4 supports 800, 850, 900, 1900, and 2100 MHz. The 800 MHz frequency, which is most commonly used in Japanese mobile phones, is not advertised as being supported by Apple. However, the 800 MHz band is a subset of the 850 MHz band, which probably explains why the device was advertised as quad-band. The chip-sets were manufactured by Skyworks Solutions and Infineon for GSM version.
As with most of Apple's mobile products at the time, the iPhone 4 also used the 30 pin dock connector as its only external data port.
The iPhone 4 is the first generation of iPhone to have a second microphone used for noise cancellation. It is located on the top of the unit near the headphone jack; the main microphone is on the bottom left.
Gyroscope and accelerometer