As the components required to build a computer system have reduced in size, new categories of computer systems have emerged. One of the more recent categories of computer systems is the portable or “palmtop” computer system, or personal digital assistant (PDA). A palmtop computer system is a computer that is small enough to be held in the hand of a user and is thus “palm”. As a result, palmtops are readily carried about in a briefcase or purse, and some palmtops are compact enough to fit into a person's pocket. By virtue of their size, palmtop computer systems are also lightweight and so are exceptionally portable and convenient.
The emergence of the cellular phone technology in the last few years has revolutionized the telecommunications industry. Where in the past telephones were largely confined to homes, offices, and other stationary structures, cellular phone technology has made it possible for phones to be truly portable and exist nearly anywhere there are people.
Recently, the technology behind both palmtop computer systems and cellular phones has advanced to the point where it is proposed to integrate cellular phone capabilities into a palmtop computer system. However, both types of devices possess different modes of operation. For example, palmtop computer systems are handheld devices providing primarily a visual experience while cellular phones are held to the head of a user and provide primarily an auditory experience.
Integrated palmtop computer systems/cellular phones present concerns regarding accessibility and immediacy. Typical integrated palmtop computer systems/cellular phones limit a user's accessibility to each distinct function of the device. For example, a user is required to hold a cellular phone to their face, thereby restricting the use of the PDA functions, which require a user to be able to look at the device.
Furthermore, a cellular phone requires an immediate response to an incoming call, or the user risks missing the call. For example, a caller will only wait a matter of seconds for a person to answer their call, otherwise they will hang up. If a user is using the PDA function of an integrated palmtop computer system/cellular phone and receives an incoming call, the user must stop using the PDA functionality in order to answer the call.
In some integrated palmtop computer system/cellular phones, a user may not be able to operate the two devices at the same time. For example, a user operating the device as a cellular phone may desire to write a note or make an appointment on the PDA. At a minimum, the user will be forced to pause the phone call. However, the user may not be permitted to operate the PDA functionality while the device is being operated as a cellular phone, thus limiting the accessibility of the PDA functionality.
The form factor of the device plays a crucial role in whether or not users are comfortable operating the device. For example, manufacturers believe that some cellular phone users may be hesitant to use a cellular phone that is in the shape of a palmtop computer system. Likewise, a typical cellular phone display does not offer the size or interface functionality that a palmtop computer system does. The users of palmtop computer systems and cellular phones desire the benefits of each of the respective devices, and are unlikely to sacrifice these benefits if forced to compromise the form factor of the device.