Terminology

The following list describes the technologies, patterns, frameworks, applications, and other terms commonly associated with developing for mobile devices such as Windows Phone 7:

• Accelerometer. A device capability that measures acceleration in three planes, and the direction of the force of gravity that indicates the attitude of the device. Can be used to detect movement, including gestures such as shaking the device.
• Advanced Encryption Standard (AES). A symmetric encryption algorithm available on Windows Phone 7 that can be used to encrypt data.
• AllKeys API. Allows your programs to request that all key presses be sent directly to the requesting application. Usually, some buttons are intercepted by the operating system for its own use, but games and input-intensive applications may want access to these buttons for their own use.
• Application bar. The small area at the bottom of the screen that contains buttons for commonly used functions of the currently executing application. This optional bar shows a set of icons by default, but the user can expand it to also show the text captions for the buttons. An application can show a maximum of four buttons on the application bar.
• Application Verifier (AppVerifier). A software test tool used to check the stability of the application and detect common programming mistakes associated with memory management. AppVerifier can detect and pinpoint memory leaks, handle leaks, and heap corruption.
• Atom Publishing Protocol (Atom Pub). An XML-based format for data that uses a Representational State Transfer (REST) architectural style where the names of collections and entities are defined in the query string of a request.
• Cloud services. Services that run in one or more remote data centers on specially designed hardware and a virtual runtime (fabric) that provides very high availability, reliability through multiple instances, performance, and scalability. Generally, cloud services are cost-effective ways to provide local and global access to applications and services without requiring the investment, expertise, maintenance, administrative overhead, and run-time cost of an on-premises server infrastructure.
• DPI. Dots-per-inch (DPI) is a measure of video dot density, in particular the number of individual dots that can be placed within the span of one linear inch (2.54 cm.). It is related to image resolution.
• Elasticity. The capability of a service, such as a cloud-based application, to be expanded by adding service instances and shrunk by removing service instances to more closely match the current requirements and load. This minimizes cost by not requiring the acquisition of sufficient hardware, software, and bandwidth to satisfy peak demand that is then idle at other times.
• File-based applications. File-based applications store data in a file and often work as editors for specific file formats. Examples include word-processors and spreadsheet applications.
• GAPI. Game API (GAPI functions) provides solutions for developers who want to write high-performance, real-time games on devices running on Windows Mobile-based devices.

Note: GAPI was deprecated in Windows Mobile 6.5, so developers should use the AllKeys, DirectDraw, and Direct3D® Mobile APIs instead.

• GPS. See “Location service.”
• Hash-based Message Authentication Code (HMAC). A keyed hash algorithm that can be used to create a non-reversible hash value for data. Two versions that use a Secure Hash Algorithm (SHA) are available on Windows Phone 7: HMACSHA1 and HMACSHA256.
• Home screen. The point from which users start most of their applications, and the point that the user can return to with a press of the Home button. In Windows Phone 7, developers can customize the Home screen by providing tile images that the user can add to the page.
• Ink Presenter control. A primitive control that can display strokes within a Canvas control.
• Location service. A phone-based service that the phone uses to discover its geographical location based on a series of factors. These factors can include the built-in GPS capability, and triangulation of public Wi-Fi networks and phone signal towers.
• Managed code. Managed code is code compiled for the .NET Framework. Managed code is often written in Visual C# or Visual Basic .NET.
• Metro theme. The standard theme used in Windows Phone 7, and recommended for applications you develop so that they integrate seamlessly with the operating system and other applications. The theme is designed to provide a modern UI that is easy to use, while minimizing power consumption on the phone.
• Microsoft Push Notification System (MPNS). A service that allows developers to send notifications to users’ phones that are displayed even if the application is not running, or will update a tile on the Start menu of the phone to indicate that new information is available.
• Model-View-ViewModel (MVVM). A design pattern particularly suited to Windows Presentation Foundation (WPF) and Silverlight applications. It uses views to implement the UI, a model that holds the data for the application, and view models that access the model and populate the views using the powerful data-binding capabilities of WPF and Silverlight. It makes it easier to decouple sections of the application, develop the
  components, test them, and maintain the application post deployment.
• MultiScale Image control. A control that can be used to display a very large image without requiring it to be fully downloaded to memory. It uses a collection of multiple sub-images at different resolutions. The control provides methods to pan and zoom over the image.
• Non file-based application. An application that does not need to store any data in a file. For example, a calculator application.
• Notifications. Messages that are sent from a server to the phone through the Windows Notification Service and can be received even when the application is not running. Notifications can display a message at the top of the screen or change a program tile on the Home screen. It is also possible to send raw notifications that the application itself must handle. Users must register to receive notifications on their phone.
• Open Data Protocol (OData). A web protocol for querying and updating data. OData builds on web technologies such as HTTP (http://www.w3.org/Protocols/), Atom Pub, and JavaScript Object Notation (JSON http://json.org/) to provide access to information from a variety of applications, services, and stores.
• Panorama control. A control that offers a way to view controls, data, and services by using a long horizontal canvas that extends beyond the confines of the screen. Areas of this canvas are viewed as smaller individual areas by panning sideways. Effectively, it provides a viewport over the larger area. The user can scroll the window horizontally across the larger view to see the complete content.
• Pivot control. A control that provides individual views over related sets of data. Typically, the individual views are related; for example, views that show new items, favorite items, and recently viewed items from the users stored photos. This control can be used to present filtered views of large data sets or to switch between application views. The user pans horizontally to navigate between the views.
• Prism. A free utility library from the Microsoft patterns & practices group. The components in this library can help developers build applications for WPF, Silverlight, and Windows Phone that are easier to maintain and update as requirements change.
• Proximity sensor. A device capability that detects whether the phone is close to an object, such as the human body. The operating system uses this to change the behavior when the device is used in phone mode.
• Push notifications. See “Notifications.”
• Representational State Transfer (REST). An architectural style used to expose data from services that allows simple access to, and optional manipulation of, information without requiring the server to maintain state between requests.
• Rfc2898DeriveBytes. An algorithm available on Windows Phone 7 that takes a password, a salt, and an iteration count, and then generates encrypted keys of virtually unlimited length. Secure Hash Algorithm (SHA). An algorithm for creating a non-reversible hash value for data. Two versions are available on Windows Phone 7: SHA1 and SHA256.
• Simple Object Access Protocol (SOAP). A protocol used to allow clients to execute methods on a remote server to obtain information or perform processing. It is an XML-based format that packages the data in a SOAP envelope. SOAP messages carry both payload and metadata, which provides for transportindependent security and reliability and can add layers of functionality to the communication, such as atomic transactions or cross-system activity tracing.
• Soft input panel. An on-screen input method (software keyboard) for devices that do not include a hardware keyboard.
• SQL Azure. A solution that offers multiple highly reliable, scalable, cloud-based relational databases where you can store data used by your services and applications. Databases are provisioned on-demand and are charged according to usage. SQL Azure is part of the Windows Azure platform.
• Secure Sockets Layer (SSL). A cryptographic protocol for securing communication between clients and services over a TCP/IP network. Often described as HTTPS, it operates by default through port 443 instead of port 80. The more recent implementation is Transport Layer Security (TLS).
• Transport Layer Security (TLS). A cryptographic protocol for securing communication between clients and services over a TCP/IP network. Provides better overall security than SSL, and is often used to secure messaging communication as well as web requests and responses.
• Tombstoning. The process whereby the currently executing application must stop to allow another application or device feature (such as an incoming phone call) to execute. The application must save its state so that it can either be continued from where it left off or be terminated without losing data.
• Touch input. Windows Phone 7 supports touch and gestures for interaction with the phone and applications running on it. It recognizes up to four touch points and gestures such as tap, double-tap, pan, flick, pinch, stretch, and touch hold.
• Windows Azure. A highly reliable, scalable, cost-effective, and elastic run-time environment within the cloud that you can use to run applications that expose services or accept web requests.
• Windows Azure Web Role. An instance of a web service running within Windows Azure that accepts connections from clients and returns responses to them while performing some processing that is appropriate to the Windows Azure service that hosts the role.
• Windows Azure Worker Role. An instance of an application service running within Windows Azure. Worker roles run asynchronously and communicate with web roles through queues or messages; generally to perform background tasks or other processing that is not part of the web role.
• Windows Marketplace. Delivers an end-to-end solution for end-users to discover, purchase, and download Windows-based applications for the desktop and mobile devices. This includes an end-user experience on the device, a website, as well as a self-service portal for developers to submit their applications for listing in Windows Marketplace.
• Windows Mobile Device Center. An application that you can use together with Windows Vista® operating system or Windows 7. It offers device management features and lets you synchronize data between a Windows Mobile-based device and a computer. Windows Mobile Device Center replaces ActiveSync® technology, which was available on earlier desktop operating systems.
• Zune Desktop Client. A desktop synchronization application that is primarily used by consumers for synchronizing music and videos, but it is also used by developers to upload applications to the phone during the development and testing processes.