A BlackBerry is a a prime example of convergent device (a device that offers services traditionally offered by separate devices or providers).

A BlackBerry has a built-in keyboard but system navigation is primarily accomplished by the trackwheel (or thumbwheel), a scrolling wheel with a "click" function. Some models utilize a trackball in the middle of the device as Research In Motion has moved from the trackwheel to the trackball.

BlackBerry handhelds are integrated into an organization's e-mail system through software called "BlackBerry Enterprise Server" (or BES). Versions of BES are available for Microsoft Exchange, Lotus Domino and Novell GroupWise. While individual users may be able to use a wireless provider's e-mail services without the need to install BES, organizations with multiple users usually run BES on their network. Some third-party companies provide hosted BES solutions.

Every BlackBerry has a unique id called BlackBerry PIN which is used to identify the device to the BES.

BES can act as a kind of e-mail relay for corporate accounts so that users always have access to their e-mail. The software monitors the user's local "inbox", and when a new message comes in, it collects the message and passes it to RIM's Network Operations Center (NOC). The messages are then relayed to the user's wireless provider, which in turn delivers them to the user's BlackBerry device.

The technology was developed by the Canadian company Research In Motion (RIM).