The iPhone 5 Brings LTE to Apple Phones

Apple announced the iPhone 5 on September 12, 2012 at the Yerba Buena Center for the Arts in San Francisco, with units available for purchase September 21. It was the first iPhone to support LTE (4G Long Term Evolution) cellular connectivity, the first with a 4-inch display, and the first to use the Lightning connector. The hardware design was notably thin at 7.6 mm (versus iPhone 4S at 9.3 mm) and 112 grams — Apple’s marketing characterized it as “the thinnest and lightest iPhone ever.” The 4-inch Retina display (1136×640 at 326 ppi) maintained the same 326 ppi pixel density as the iPhone 4/4S while adding 176 rows of pixels, switching from a 3:2 to a 16:9 aspect ratio that matched the aspect ratio of widescreen video — meaning iPhone 5 could display 1080p HD video content without letterboxing on the sides. The Apple A6 SoC was Apple’s first processor using custom-designed CPU cores (codenamed Swift) rather than standard ARM Cortex implementations licensed from ARM Holdings, clocked at 1.3 GHz in a dual-core configuration, delivering approximately 2× CPU and 2× GPU performance versus the A5 in iPhone 4S. The A6 packaged 1 GB LPDDR2 RAM and a PowerVR SGX543MP3 GPU. LTE was supported through a Qualcomm MDM9615 modem, which for the first time combined GSM/UMTS and CDMA radio support in a single chip, enabling Apple to consolidate what had previously been separate hardware variants for AT&T and Verizon/Sprint into a smaller number of antenna configurations.

LTE’s practical significance for users was a roughly 10× increase in peak data throughput compared to HSPA+ 3G in good coverage areas — theoretical maximum 100 Mbps downlink on LTE versus 21 Mbps on HSPA+ — enabling HD video streaming, fast web page loading, and FaceTime over cellular (which Apple enabled on LTE in iOS 6, having previously required Wi-Fi). The engineering challenge of adding LTE while maintaining battery life had been a key reason Apple waited until iPhone 5: earlier Android LTE phones, including HTC’s Thunderbolt (March 2011) and Samsung Galaxy Nexus (December 2011), were notorious for battery drain because they used separate baseband chips for LTE alongside existing 3G modems, adding both power consumption and heat. Qualcomm’s MDM9615 combined both in a more power-efficient package, and Apple’s power management engineering reduced the LTE radio’s active-state power draw sufficiently that the iPhone 5 matched the iPhone 4S’s battery life (8 hours talk time on 3G/LTE) despite the larger display and additional radio complexity. The iPhone 5 was also designed with three hardware variants (A1428, A1429, A1442) supporting different LTE band combinations for different carrier/region combinations, as LTE spectrum allocations varied significantly between countries and carriers.

The Lightning connector replaced the 30-pin Dock Connector that Apple had introduced with the third-generation iPod in October 2001 — an 11-year standard that had accumulated a large ecosystem of accessories, docks, speaker systems, and charging cables. Lightning was significantly smaller (8 pins, compared to 30-pin’s footprint), reversible (either orientation worked), and more durable (no exposed pins on the connector side). The transition invalidated the accessory ecosystem accumulated over eleven years; Apple offered a $29 30-pin to Lightning adapter but noted that it did not support some legacy accessories due to hardware limitations. The accessory makers who had built businesses around the 30-pin standard faced a hardware transition similar to what PC peripheral makers faced with USB adoption in the late 1990s. Simultaneously, iPhone 5 launched with iOS 6 and Apple Maps — Apple’s first-party mapping application replacing Google Maps as the default, built using data from TomTom and other mapping providers. Apple Maps at launch had significant data quality problems including missing transit directions, incorrect business locations, and a widely-mocked 3D flyover mode that rendered some buildings as melted shapes; the backlash prompted an unusual public apology from Tim Cook on September 28, 2012, and Apple CEO Tim Cook suggested users try Google Maps and other mapping alternatives, which had rarely if ever been recommended by Apple for competing with a built-in Apple app.