When you purchase an iPhone, you can get any kind of iPhone you want, as long as it's black. When you purchase an Android smart phone, you have far more choices--too many, in my opinion--including a host of models, a choice of wireless carriers, and an ever-expanding range of OS version numbers, each with a unique set of functionality.
With Windows Phone, Microsoft has tried to split the difference. It offers more choice than does Apple, from both model selection and wireless carrier perspectives. But it also provides users with the comfort of knowing that each Windows Phone will provide a consistent hardware and software experience, unlike with Android. It really is the best of both worlds.
When it comes to the hardware available on Windows Phones, Microsoft has established a minimum specification for its so-called Chassis-1 design, which applies to all currently-available Windows Phones. In early 2011, device makers will begin shipping phones based on a second, Chassis-2, design, which differs only slightly, as I'll mention throughout this article when necessary. But in either case, what you're getting with Windows Phone is the makings of a high-end portable device.
That said, there's some confusion over which hardware features are included with all Windows Phones, which features are optional, and which aren't happening at all, at least in this first generation of devices. So let's take a look at each.
Hardware features that are included with all Windows Phones
According to Microsoft, every Windows Phone must include at least the following hardware components:
Microprocessor (CPU). All Windows Phones must provide at least a 1 GHz ARMv7 Cortex/Scorpion or better processor.
Graphics (GPU). Windows Phones ship with a DirectX 9-capable graphics processing unit, or GPU. This provides your phone with exactly the same graphical capabilities--from a visual perspective--as is possible with Microsoft's Xbox 360 video game console. The result is stunning visuals and the possibility of seeing games ported from the console to the phone in full graphical fidelity. (Actually gameplay is another matter, given the input differences.)
RAM and storage. Each Windows Phone includes at least 256 MB of RAM (memory allotted for the operating system and running applications) and 8 GB or more of Flash storage (for content, including applications, digital media, documents, and the like).
Hardware buttons. Every Windows Phone comes with a dedicated set of hardware buttons positioned in a consistent way around the device. These include Back, Home, and Search buttons (for navigating "back" as per a web browser, returning to the Home screen, and launching the Bing search experience, respectively), a dedicated camera button (with full and half press support for launching the camera application, auto-focusing, and taking photos), volume up and volume down (two separate buttons), and power/sleep (with brief and full press support for dimming the screen, waking up the device, and so on).
Secret: The Back, Start, and Search buttons can optionally be implemented as capacitive touch buttons by devices makers. The other buttons must be hardware buttons.
Secret: If you receive a phone call, touching either volume button will silence the ring.
Camera. Microsoft requires hardware makers to include at least a 5 megapixel (MPX) camera with flash (and, as noted above, a dedicated camera button).
Capacitive multi-touch display with four or more contact points. Like the iPhone, Windows Phones are primarily touch-based devices with virtual keyboards that work in both portrait and landscape modes. The screens offer touch and multi-touch capabilities, of course, with up to four contact points. That means you could theoretically place four fingers on the screen, each doing something different, and the device could accurately process that information and act accordingly. The Windows Phone screen supports gestures as well.
Chassis-1 devices (which are all Windows Phones currently on the market) support a screen resolution of 800 x 480 (WVGA) only, with at least 16-bit color. Chassis-2 devices, due in 2011, will provide a 480 x 320 (HWVGA) resolution only, with at least 16-bit color.
Accelerometer. First popularized by the iPhone, an accelerometer is an internal component that can measure acceleration along multiple axis. What this means to you is that a Windows Phone can detect, and respond to, the device being tilted in different directions. The accelerometer is used in ways both utilitarian--if you rotate the device, the display will rotate to accommodate the new orientation--and far less practical--in a racing game, for example, tilting the screen left to right as you play could steer the car.
Assisted GPS (A-GPS). Windows Phones ship with the latest GPS (global positioning system) hardware, providing quicker startup and better accuracy, the latter of which is key to a US-based requirement that will allow 911 dispatchers to find smart phone users in an emergency.
Compass. Windows Phones ship with an internal compass, which works in concert with the GPS and other location sensors (including Wi-Fi and cellular connection) to accurately find your location and supply information about the direction you are facing.
Light sensor. Thanks to the built-in light sensor, the Windows Phone camera can accurately gauge illumination requirements for the flash and produce accurate and clear low-light photos.
Proximity sensor. This sensor can detect how close other objects--like your face or a table--are to the phone. So the phone can know when you're making a phone call or when you've placed the device on a table. And unlike the proximity sensor in the iPhone 4, Windows Phone's sensor actually works.
FM radio tuner. All Windows Phones ship with an FM radio tuner, providing free access to FM radio and, via bundled software, the ability to mark particular stations as favorites.
Hardware features that are not included with every Windows Phone
You may have noticed that the Windows Phone hardware requirement list above doesn't include some hardware features that you believe are important or even necessary in a modern smart phone. In some cases, these omissions are nothing to worry about: Hardware makers are free to exceed Microsoft's requirements and they all do currently bundle additional features with their phones. In other cases, however, the lack of certain features is a bit more troubling, because the underlying platform simply doesn't support this hardware.
Here are some features that Microsoft--good, bad, or indifferently--does not explicitly require its phone makers to include with a Windows Phone.
Wi-Fi. Despite its absence from the hardware requirement list, virtually every Windows Phone will include 802.11g (Wi-Fi G) or 802.11n (Wi-Fi N) wireless networking capabilities. To my knowledge, all generation one hardware does support this feature.
Bluetooth. Ditto for Bluetooth, a separate wireless networking standard that is most often used to connect portable devices with in-ear headsets, keyboards, in-car navigation systems, and other hardware.
Removable storage. Most non-iPhone smart phones (and virtually all popular Android-based phones) ship with some kind of memory card slot (typically micro-SD) so that you can inexpensively expand the device's internal storage (but not RAM). Today, these mini memory cards typically range from 2 GB to 32 GB of storage, but of course, technology improves as time marches on. Windows Phone does not support removable storage. It does, however, support expandable storage, and device makers are free to include a micro-SD card slot under the battery cover that enables this functionality. Note that this feature is not supported by Microsoft but is instead supported by your wireless carrier.
Ultra high resolution screens and custom resolutions. The iPhone 4 supports a resolution of 960 x 640, which exceeds the highest resolution supported by Windows Phone. While there is little doubt that the Windows Phone OS could handle higher (or different) resolutions, device makers are prohibited from selling such a device at this time. As Microsoft evolves the Windows Phone hardware requirements over time, this limitation will change. But don't ever expect to see a wide range of resolution options.
Gyroscope. While Windows Phone does include an accelerometer, it is lacking a gyroscope, a hardware component that is also found in the iPhone 4. Speaking simply--because, let's face it, this is complicated stuff--a gyroscope simply provides a more accurate, or more sensitive, measurement of how the device is being rotated in X, Y, or Z axis (or "directions"). Given the relatively non-subtle hand movements that will be typical in human/phone interaction, I do not feel that a gyroscope is a particularly important improvement over an accelerometer and that its loss will not impact the Windows Phone experience, gaming or otherwise. But it is a missing feature.
Camera with video recording capabilities. While Microsoft doesn't specify that the Windows Phone camera be able to record video, virtually all Windows Phones do, in fact, ship with this capability. Expect VGA (640p) or HD (720p) or better video recording capabilities.
Camera with geo-tagging capabilities. Another neat camera feature, geo-tagging allows your camera to optionally "tag" each photo with location data so that you can later discover exactly where the photo was taken on a map. This capability is absolutely possible with Windows Phone, thanks to its built-in GPS and other location sensors, and is in fact a feature of the built-in camera software. So no worries here: Most Windows Phones do support this feature.
Headphone jack, microphone, and external speaker(s). While Microsoft does not require Windows Phone hardware makers to include a standard headphone jack, microphone, or external speaker(s) on their devices, most of course will do so. Be sure to look for these features, however.
Second, front-facing camera. While all Windows Phones ship with a single, high-quality camera, Microsoft provides no underlying support for a second, front-facing camera that could be used for video conferencing. It's possible that we will see such functionality occur over time, either because Microsoft provides platform support for it, or via a third party that provides unique software for such usage.
USB connection. While all Windows Phones will need to provide some way to charge the device, Microsoft does not specify the type of connection that will be used. The result is that different Windows Phones unfortunately could use different power/charge connections. But in reality, most simply use micro-USB. In conjunction with a compatible
Zune connector. One useful feature that Microsoft is not supporting, let alone requiring, is the Zune dock connector that the company previous used on its line of Zune portable media players. This connector worked exactly like Apple's popular dock connector, which provides iPod, iPad, and iPhone users with a standard connector type. You will not find a Windows Phone with a Zune dock connector.
Hardware keyboard. While all Windows Phones include a nicely-tuned virtual ("soft") keyboard, device makers can also optionally provide a hardware keyboard in either vertical (portrait) or horizontal (landscape) orientation.
Secret: Windows Phone 7 keyboard (hardware and software) supports only full alphabet layouts such as QWERTY, AZERTY, and QWERTZ. 12- or 20-key layouts are not supported.
Secret: The hardware keyboard is only used for typing letters, accented letters, numbers and symbols, and cannot be used to control the user interface.
Unlocked phones. Microsoft is allowing device makers to create unlocked versions of their phones. At the time of this writing, none of the US-based Windows Phones are available in unlocked form, but some international models are. This will likely change over time.