The Evo 4G and the HD2 are both smartphones that HTC released in 2010. However, while the two smartphones have the same manufacturer and have some similar hardware features, they vary in terms of performance. According to CNET Reviews, as of 2011, the HTC Evo 4G is "today's top Android device" and is "Sprint's best smartphone", while the HTC HD2, despite having an outdated operating system, is the most "powerful" and "entertaining smartphone in T-Mobile's lineup."
Cellular Technology
Unlike the HTC HD2, which utilizes third-generation (3G) cellular technology, the HTC Evo 4G utilizes fourth-generation (4G) cellular technology. 4G technology allows the Evo 4G to stream video and other multimedia from the Internet -- without needing to connect to a Wi-Fi hotspot -- more rapidly than the HD2 can. Specifically, the Evo 4G operates over Sprint's Worldwide Interoperability for Microwave Access (WiMAX) network, allowing the smartphone to achieve download speeds of over 10 megabits per second (Mbps) and upload speeds of up to 1 Mbps. However, in areas where WiMAX is not yet available, the Evo 4G relies on Sprint's Code Division Multiple Access (CDMA) 200 1X 3G network. In contrast, the HD2 can operate over T-Mobile's Wideband Code Division Multiple Access (WCDMA), Universal Mobile Telecommunications System (UMTS) 3G network or over T-Mobile's second-generation (2G) Global System for Mobile Communications (GSM) network.
Physical Specifications
The physical specifications of the HTC Evo 4G and the HTC HD2 are similar, although the Evo 4G is a bit thicker and a bit heavier. While the Evo 4G has dimensions of 2.6 inches wide by 4.8 inches tall by 0.5 inches thick and weighs 6.2 oz., the HD2 has dimensions of 2.6 inches wide by 4.8 inches tall by 0.4 inches thick and weighs 5.5 oz.
Display
Both the HTC Evo 4G and the HTC HD2 utilize thin film transistor (TFT) displays, which are active-matrix varieties of liquid crystal displays (LCDs). In addition, both displays have diagonal sizes of 4.3 inches and display resolutions of 800 horizontal lines of pixels by 480 vertical lines of pixels. Unlike the HD2, however, the Evo 4G features a miniature kickstand on its back, which allows users to prop-up the smartphone's display for hands-free viewing.
Operating System
The HTC Evo 4G utilizes Google's Android 2.1 mobile operating system, while HTC HD2 utilizes Microsoft's Windows Mobile 6.5 operating system. While both operating systems have their benefits, one main advantage of Android 2.1 is that it provides users with access to the Android Market for purchasing third-party applications. In addition, Android 2.1 supplies many Google services, such as Google Maps with navigation.
Camera
The camera of the HTC Evo 4G offers better resolution than the HTC HD2's camera. While the Evo 4G's camera can capture still images in 8 megapixels, or 8 million tiny squares of illumination, the HD2's camera can only capture still images in 5 megapixels, or 5 million tiny squares of illumination.
Tags: capture still, capture still images, Code Division, Code Division Multiple, dimensions inches, dimensions inches wide, Division Multiple