Mobile computing is human–computer interaction in which a computer is expected to be transported during normal usage, which allows for the transmission of data, voice, and video. Mobile computing involves mobile communication, mobile hardware, and mobile software. Communication issues include ad hoc networks and infrastructure networks as well as communication properties, protocols, data formats, and concrete technologies. Hardware includes mobile devices or device components. Mobile software deals with the characteristics and requirements of mobile applications.

Main principles

* Portability: Devices/nodes connected within the mobile computing system should facilitate mobility. These devices may have limited device capabilities and limited power supply but should have a sufficient processing capability and physical portability to operate in a movable environment. * Connectivity: This defines the

quality of service Quality of service (QoS) is the description or measurement of the overall performance of a service, such as a telephony or computer network, or a cloud computing service, particularly the performance seen by the users of the network. To quantitat ...

(QoS) of the network connectivity. In a mobile computing system, the network availability is expected to be maintained at a high level with a minimal amount of lag/downtime without being affected by the mobility of the connected nodes. * Interactivity: The nodes belonging to a mobile computing system are connected with one another to communicate and collaborate through active transactions of data. * Individuality: A portable device or a mobile node connected to a mobile network often denotes an individual; a mobile computing system should be able to adopt the technology to cater to the individual needs and also to obtain contextual information of each node.

Devices

Some of the most common forms of mobile computing devices are as given below: * Portable computers, compact, lightweight units including a full character set keyboard and primarily intended as

host A host is a person responsible for guests at an event or for providing hospitality during it. Host may also refer to: Places * Host, Pennsylvania, a village in Berks County People *Jim Host (born 1937), American businessman * Michel Host ...

s for software that may be parameterized, such as

laptop A laptop, laptop computer, or notebook computer is a small, portable personal computer (PC) with a screen and alphanumeric keyboard. Laptops typically have a clam shell form factor with the screen mounted on the inside of the upper li ...

s/ desktops,

smartphones A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, which ...

/ tablets, etc. *

Smart card A smart card, chip card, or integrated circuit card (ICC or IC card) is a physical electronic authentication device, used to control access to a resource. It is typically a plastic credit card-sized card with an embedded integrated circuit (IC) c ...

s that can run multiple applications but are typically used for payment, travel, and secure area access. *

Mobile phone A mobile phone, cellular phone, cell phone, cellphone, handphone, hand phone or pocket phone, sometimes shortened to simply mobile, cell, or just phone, is a portable telephone that can make and receive calls over a radio frequency link whil ...

s, telephony devices which can

call Call or Calls may refer to: Arts, entertainment, and media Games * Call, a type of betting in poker * Call, in the game of contract bridge, a bid, pass, double, or redouble in the bidding stage Music and dance * Call (band), from Lahore, Paki ...

from a distance through cellular networking technology. *

Wearable computer A wearable computer, also known as a body-borne computer, is a computing device worn on the body. The definition of 'wearable computer' may be narrow or broad, extending to smartphones or even ordinary wristwatches. Wearables may be for general ...

s, mostly limited to functional keys and primarily intended for the incorporation of

software agent In computer science, a software agent or software AI is a computer program that acts for a user or other program in a relationship of agency, which derives from the Latin ''agere'' (to do): an agreement to act on one's behalf. Such "action on behal ...

s, such as bracelets, keyless implants, etc. Apple Watch-

These classes are expected to endure and to complement each other, none replacing another completely. Other types of mobile computers have been introduced since the 1990s, including the: *

Portable computer A portable computer is a computer designed to be easily moved from one place to another and included a display and keyboard together, with a single plug, much like later desktop computers called '' all-in-ones'' (AIO), that integrate the s ...

(discontinued) *

Personal digital assistant A personal digital assistant (PDA), also known as a handheld PC, is a variety mobile device which functions as a personal information manager. PDAs have been mostly displaced by the widespread adoption of highly capable smartphones, in partic ...

/ Enterprise digital assistant (discontinued) *

Ultra-Mobile PC An ultra-mobile PC, or ultra-mobile personal computer (UMPC), is a miniature version of a pen computer, a class of laptop whose specifications were launched by Microsoft and Intel in spring 2006. Sony had already made a first attempt in this d ...

(discontinued) *

Laptop A laptop, laptop computer, or notebook computer is a small, portable personal computer (PC) with a screen and alphanumeric keyboard. Laptops typically have a clam shell form factor with the screen mounted on the inside of the upper li ...

Smartphone A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, whic ...

and

tablet computer A tablet computer, commonly shortened to tablet, is a mobile device, typically with a mobile operating system and touchscreen display processing circuitry, and a rechargeable battery in a single, thin and flat package. Tablets, being comput ...

E-reader An e-reader, also called an e-book reader or e-book device, is a mobile electronic device that is designed primarily for the purpose of reading digital e-books and periodicals. Any device that can display text on a screen may act as an e-read ...

Carputer A carputer, or car-puter, is a computer with specializations to run in a car, such as compact size, low power requirement, and some customized components. The computing hardware is typically based on standard PCs or mobile devices. They normally ha ...

Limitations

* Expandability, replaceability and modularity: In contrast to the common traditional

motherboard A motherboard (also called mainboard, main circuit board, mb, mboard, backplane board, base board, system board, logic board (only in Apple computers) or mobo) is the main printed circuit board (PCB) in general-purpose computers and other expand ...

-based PC the SoC architecture in which they are embedded makes these features impossible. * Lack of a

BIOS In computing, BIOS (, ; Basic Input/Output System, also known as the System BIOS, ROM BIOS, BIOS ROM or PC BIOS) is firmware used to provide runtime services for operating systems and programs and to perform hardware initialization during the ...

: As most smart devices lack a proper

, their bootloading capabilities are limited as they can only boot into the single

operative system An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also in ...

with which it came, in contrast with the PC BIOS model. * Range and bandwidth: Mobile Internet access is generally slower than direct cable connections, using technologies such as GPRS and

EDGE Edge or EDGE may refer to: Technology Computing * Edge computing, a network load-balancing system * Edge device, an entry point to a computer network * Adobe Edge, a graphical development application * Microsoft Edge, a web browser developed by ...

, and more recently

HSDPA High Speed Packet Access (HSPA) is an amalgamation of two mobile protocols—High Speed Downlink Packet Access (HSDPA) and High Speed Uplink Packet Access (HSUPA)—that extends and improves the performance of existing 3G mobile telecommunic ...

HSUPA High Speed Packet Access (HSPA) is an amalgamation of two mobile protocols—High Speed Downlink Packet Access (HSDPA) and High Speed Uplink Packet Access (HSUPA)—that extends and improves the performance of existing 3G mobile telecommunic ...

, 3G and 4G networks and also the proposed 5G network. These networks are usually available within a range of commercial cell phone towers. High-speed network wireless LANs are inexpensive but have a very limited range. * Security standards: When working mobile, one is dependent on public networks, requiring careful use of

VPN A virtual private network (VPN) extends a private network across a public network and enables users to send and receive data across shared or public networks as if their computing devices were directly connected to the private network. The be ...

. Security is a major concern while concerning the mobile computing standards on the fleet. One can easily attack the VPN through a huge number of networks interconnected through the line. * Power consumption: When a power outlet or portable generator is not available, mobile computers must rely entirely on battery power. Combined with the compact size of many mobile devices, this often means unusually expensive batteries must be used to obtain the necessary battery life. * Transmission interferences: Weather, terrain, and the range from the nearest signal point can all interfere with signal reception. Reception in tunnels, some buildings, and rural areas is often poor. * Potential health hazards: People who use mobile devices while driving are often distracted from driving and are thus assumed more likely to be involved in traffic accidents. (While this may seem obvious, there is considerable discussion about whether banning mobile device use while driving reduces accidents.) Cell phones may interfere with sensitive medical devices. Questions concerning

mobile phone radiation and health The antennas contained in mobile phones, including smartphones, emit radiofrequency (RF) radiation ( non-ionizing "radio waves" such as microwaves); the parts of the head or body nearest to the antenna can absorb this energy and convert it t ...

have been raised. * Human interface with device: Screens and keyboards tend to be small, which may make them hard to use. Alternate input methods such as speech or

handwriting recognition Handwriting recognition (HWR), also known as handwritten text recognition (HTR), is the ability of a computer to receive and interpret intelligible handwritten input from sources such as paper documents, photographs, touch-screens and other dev ...

require training.

In-vehicle computing and fleet computing

Many commercial and government field forces deploy a rugged portable computer with their fleet of vehicles. This requires the units to be anchored to the vehicle for driver safety, device security, and

ergonomics Human factors and ergonomics (commonly referred to as human factors) is the application of psychological and physiological principles to the engineering and design of products, processes, and systems. Four primary goals of human factors learnin ...

Rugged computer A rugged computer or ruggedized computer is a computer specifically designed to operate reliably in harsh usage environments and conditions, such as strong vibrations, extreme temperatures and wet or dusty conditions. They are designed from incepti ...

s are rated for severe vibration associated with large service vehicles and off-road driving and the harsh environmental conditions of constant professional use such as in

emergency medical services Emergency medical services (EMS), also known as ambulance services or paramedic services, are emergency services that provide urgent pre-hospital treatment and stabilisation for serious illness and injuries and transport to definitive care. ...

, fire, and public safety. Other elements affecting function in the vehicle: *

Operating temperature An operating temperature is the allowable temperature range of the local ambient environment at which an electrical or mechanical device operates. The device will operate effectively within a specified temperature range which varies based on the de ...

: A vehicle cabin can often experience temperature swings from . Computers typically must be able to withstand these temperatures while operating. Typical fan-based cooling has stated limits of of ambient temperature and temperatures below freezing require localized heaters to bring components up to operating temperature (based on independent studies by the SRI Group and by Panasonic R&D). * Vibration can decrease the life expectancy of computer components, notably rotational storage such as HDDs. * Visibility of standard screens becomes an issue in bright sunlight. * Touchscreen users easily interact with the units in the field without removing gloves. * High-temperature battery settings: Lithium-ion batteries are sensitive to high-temperature conditions for charging. A computer designed for the mobile environment should be designed with a high-temperature charging function that limits the charge to 85% or less of capacity. * External antenna connections go through the typical metal cabins of vehicles which would block wireless reception and take advantage of much more capable external communication and navigation equipment.

Security issues involved in mobile

Mobile security Mobile security, or mobile device security, is the protection of smartphones, tablets, and laptops from threats associated with wireless computing. It has become increasingly important in mobile computing. The security of personal and business ...

has become increasingly important in mobile computing. It is of particular concern as it relates to the

security Security is protection from, or resilience against, potential harm (or other unwanted coercive change) caused by others, by restraining the freedom of others to act. Beneficiaries (technically referents) of security may be of persons and social ...

of personal information now stored on the

smartphone A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, whic ...

. Mobile applications might copy user data from these devices to a remote server without the users’ permission and often without the users’ consent. The user profiles automatically created in the cloud for smartphone users raise

privacy Privacy (, ) is the ability of an individual or group to seclude themselves or information about themselves, and thereby express themselves selectively. The domain of privacy partially overlaps with security, which can include the concepts of a ...

concerns on all major platforms, in terms of, including, but not limited to,

location tracking A positioning system is a system for determining the position of an object in space. One of the most well-known and commonly used positioning systems is the Global Positioning System (GPS). Positioning system technologies exist ranging from worl ...

and personal data collection, regardless of user settings on the device. More and more users and businesses use smartphones as a means of planning and organizing their work and private life. Within companies, these technologies are causing profound changes in the organization of

information systems An information system (IS) is a formal, sociotechnical, organizational system designed to collect, process, information storage, store, and information distribution, distribute information. From a sociotechnical perspective, information systems a ...

and therefore they have become the source of new risks. Indeed, smartphones collect and compile an increasing amount of sensitive information to which access must be controlled to protect the

of the user and the

intellectual property Intellectual property (IP) is a category of property that includes intangible creations of the human intellect. There are many types of intellectual property, and some countries recognize more than others. The best-known types are patents, cop ...

of the company. All smartphones are preferred targets of attacks. These attacks exploit weaknesses related to smartphones that can come from means of wireless telecommunication like WiFi networks and

GSM The Global System for Mobile Communications (GSM) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation ( 2G) digital cellular networks used by mobile devices such ...

. There are also attacks that exploit software vulnerabilities from both the web browser and operating system. Finally, there are forms of

malicious software Malware (a portmanteau for ''malicious software'') is any software intentionally designed to cause disruption to a computer, server, client, or computer network, leak private information, gain unauthorized access to information or systems, ...

that rely on the weak knowledge of average users. Different security counter-measures are being developed and applied to smartphones, from security in different layers of software to the dissemination of information to end-users. There are good practices to be observed at all levels, from design to use, through the development of

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also in ...

s, software layers, and downloadable apps.

Portable computing devices

Several categories of portable computing devices can run on batteries but are not usually classified as laptops: portable computers, PDAs, ultra mobile PCs (UMPCs), tablets, and smartphones. * A

portable computer A portable computer is a computer designed to be easily moved from one place to another and included a display and keyboard together, with a single plug, much like later desktop computers called '' all-in-ones'' (AIO), that integrate the s ...

(discontinued) is a general-purpose computer that can be easily moved from place to place, but cannot be used while in transit, usually because it requires some "setting-up" and an AC power source. The most famous example is

Osborne 1 The Osborne 1 is the first commercially successful portable computer, released on April 3, 1981 by Osborne Computer Corporation. It weighs , cost US$1,795, and runs the CP/M 2.2 operating system. It is powered from a wall socket, as it has no on- ...

. Portable computers are also called a "transportable" or a "luggable" PC. * A

personal digital assistant A personal digital assistant (PDA), also known as a handheld PC, is a variety mobile device which functions as a personal information manager. PDAs have been mostly displaced by the widespread adoption of highly capable smartphones, in partic ...

(PDA) (discontinued) is a small, usually pocket-sized, computer with limited functionality. It is intended to supplement and to synchronize with a desktop computer, giving access to contacts, address book, notes, e-mail, and other features. * An

ultra mobile PC An ultra-mobile PC, or ultra-mobile personal computer (UMPC), is a miniature version of a pen computer, a class of laptop whose specifications were launched by Microsoft and Intel in spring 2006. Sony had already made a first attempt in this ...

(discontinued) is a full-featured, PDA-sized computer running a general-purpose operating system. * Tablets/

phones A telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most efficiently the human voice, into ele ...

: a slate tablet is shaped like a paper notebook. Smartphones are the same devices as tablets, however, the only difference with smartphones is that they are much smaller and pocketable. Instead of a physical keyboard, these devices have a

touchscreen A touchscreen or touch screen is the assembly of both an input ('touch panel') and output ('display') device. The touch panel is normally layered on the top of an electronic visual display of an information processing system. The display is often ...

including a combination of a

virtual keyboard A virtual keyboard is a software component that allows the Input device, input of characters without the need for physical keys. The interaction with the virtual Computer keyboard, keyboard happens mostly via a touchscreen interface, but can also ...

but can also link to a physical keyboard via wireless

Bluetooth Bluetooth is a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks (PANs). In the most widely used mode, transmission power is limi ...

or USB. These devices include features other computer systems would not be able to incorporate, such as built-in cameras, because of their portability - although some laptops possess camera integration, and desktops and laptops can connect to a

webcam A webcam is a video camera which is designed to record or stream to a computer or computer network. They are primarily used in videotelephony, livestreaming and social media, and security. Webcams can be built-in computer hardware or peripheral d ...

by way of USB. * A

carputer A carputer, or car-puter, is a computer with specializations to run in a car, such as compact size, low power requirement, and some customized components. The computing hardware is typically based on standard PCs or mobile devices. They normally ha ...

is installed in an automobile. It operates as a wireless computer, sound system, GPS, and DVD player. It also contains word processing software and is Bluetooth compatible. * A Pentop (discontinued) is a computing device the size and shape of a pen. It functions as a writing utensil, MP3 player, language translator, digital storage device, and calculator. * An application-specific computer is one that is tailored to a particular application. For example,

Ferranti Ferranti or Ferranti International plc was a UK electrical engineering and equipment firm that operated for over a century from 1885 until it went bankrupt in 1993. The company was once a constituent of the FTSE 100 Index. The firm was known ...

introduced a handheld application-specific mobile computer (the MRT-100) in the form of a

clipboard A clipboard is a thin, rigid board with a clip at the top for holding paper in place. A clipboard is typically used to support paper with one hand while writing on it with the other, especially when other writing surfaces are not available. Th ...

for conducting

opinion polls An opinion poll, often simply referred to as a survey or a poll (although strictly a poll is an actual election) is a human research survey of public opinion from a particular sample. Opinion polls are usually designed to represent the opinions ...

. Boundaries that separate these categories are blurry at times. For example, the

OQO OQO was a U.S. computer hardware company that was notable for manufacture of handheld computers. Its systems possessed the functionality of a tablet computer, tablet PC in a size slightly larger than a personal digital assistant (PDA). According t ...

UMPC is also a PDA-sized tablet PC; the Apple eMate had the clamshell form factor of a laptop but ran PDA software. The

HP Omnibook HP OmniBook was a range of laptop personal computers created by Hewlett-Packard, introduced in 1993. The range was discontinued following the acquisition of Compaq by Hewlett-Packard in 2002, with the Compaq Presario, HP Compaq, and HP Pavilion l ...

line of laptops included some devices small enough to be called ultra mobile PCs. The hardware of the

Nokia 770 The Nokia 770 Internet Tablet is a wireless Internet appliance from Nokia, originally announced at the LinuxWorld Summit in New York City on 25 May 2005. It is designed for wireless Internet browsing and email functions and includes software suc ...

internet tablet is essentially the same as that of a PDA such as the

Zaurus The Sharp Zaurus is the name of a series of personal digital assistants (PDAs) made by Sharp Corporation. The Zaurus was the most popular PDA during the 1990s in Japan and was based on a proprietary operating system. The first Sharp PDA to use ...

6000; the only reason it's not called a PDA is that it does not have PIM software. On the other hand, both the 770 and the Zaurus can run some desktop Linux software, usually with modifications.

Mobile data communication

Wireless Wireless communication (or just wireless, when the context allows) is the transfer of information between two or more points without the use of an electrical conductor, optical fiber or other continuous guided medium for the transfer. The most ...

data connections used in mobile computing take three general forms.

Cellular Cellular may refer to: *Cellular automaton, a model in discrete mathematics * Cell biology, the evaluation of cells work and more * ''Cellular'' (film), a 2004 movie *Cellular frequencies, assigned to networks operating in cellular RF bands *Cell ...

data service uses technologies

CDMA Code-division multiple access (CDMA) is a channel access method used by various radio communication technologies. CDMA is an example of multiple access, where several transmitters can send information simultaneously over a single communicatio ...

or GPRS, 3G networks such as

W-CDMA The Universal Mobile Telecommunications System (UMTS) is a third generation mobile cellular system for networks based on the GSM standard. Developed and maintained by the 3GPP (3rd Generation Partnership Project), UMTS is a component of the Inte ...

CDMA2000 CDMA2000 (also known as C2K or IMT Multi‑Carrier (IMT‑MC)) is a family of 3G mobile technology standards for sending voice, data, and signaling data between mobile phones and cell sites. It is developed by 3GPP2 as a backwards-compatible ...

. and more recently 4G and 5G networks. These networks are usually available within range of commercial

cell towers A cell site, cell tower, or cellular base station is a cellular-enabled mobile device site where antennas and electronic communications equipment are placed (typically on a radio mast, tower, or other raised structure) to create a cell, or adj ...

Wi-Fi Wi-Fi () is a family of wireless network protocols, based on the IEEE 802.11 family of standards, which are commonly used for local area networking of devices and Internet access, allowing nearby digital devices to exchange data by radio wave ...

connections offer higher performance, may be either on a private business network or accessed through public

hotspots Hotspot, Hot Spot or Hot spot may refer to: Places * Hot Spot, Kentucky, a community in the United States Arts, entertainment, and media Fictional entities * Hot Spot (comics), a name for the DC Comics character Isaiah Crockett * Hot Spot (Tra ...

, and have a typical range of 100 feet indoors and up to 1000 feet outdoors. Satellite Internet access covers areas where cellular and Wi-Fi are not available and may be set up anywhere the user has a

line of sight The line of sight, also known as visual axis or sightline (also sight line), is an imaginary line between a viewer/observer/ spectator's eye(s) and a subject of interest, or their relative direction. The subject may be any definable object taken ...

to the satellite's location, which for satellites in geostationary orbit means having an unobstructed view of the southern sky. Some enterprise deployments combine networks from multiple cellular networks or use a mix of cellular, Wi-Fi and satellite. When using a mix of networks, a

mobile virtual private network A mobile virtual private network (mobile VPN or mVPN) is a VPN which is capable of persisting during sessions across changes in physical connectivity, point of network attachment, and IP address.Phifer, Lisa"Mobile VPN: Closing the Gap" ''SearchMob ...

(

mobile VPN Mobile may refer to: Places * Mobile, Alabama, a U.S. port city * Mobile County, Alabama * Mobile, Arizona, a small town near Phoenix, U.S. * Mobile, Newfoundland and Labrador Arts, entertainment, and media Music Groups and labels * Mobile ...

) not only handles the

concerns, but also performs the multiple network

login In computer security, logging in (or logging on, signing in, or signing on) is the process by which an individual gains access to a computer system by identifying and authenticating themselves. The user credentials are typically some fo ...

s automatically and keeps the application connections alive to prevent crashes or data loss during network transitions or coverage loss.Phifer, Lisa
"Mobile VPN: Closing the Gap"
''SearchMobileComputing.com'', July 16, 2006. Cheng, Roger
"Lost Connections"
''

The Wall Street Journal ''The Wall Street Journal'' is an American business-focused, international daily newspaper based in New York City, with international editions also available in Chinese and Japanese. The ''Journal'', along with its Asian editions, is published ...

'', December 11, 2007.

References

Footnotes

Bibliography

* GH Forman, J Zahorjan - Computer, 1994 - doi.ieeecomputersociety.org * David P. Helmbold, "A dynamic disk spin-down technique for mobile computing", citeseer.ist.psu.edu, 1996 * MH Repacholi, "health risks from the use of mobile phones",

Toxicology Letters ''Toxicology Letters'' is a Peer review, peer-reviewed scientific journal for the rapid publication of short reports on all aspects of toxicology, especially mechanisms of toxicity. Toxicology Letters is the official journal of Eurotox.

, 2001 - Elsevier * Landay, J.A. Kaufmann, T.R., "user interface issues in mobile computing", Workstation Operating Systems, 1993. * * * * * Roth, J. "Mobile Computing - Grundlagen, Technik, Konzepte", 2005, dpunkt.verlag, Germany * Pullela, Srikanth. "Security Issues in Mobile Computing" http://crystal.uta.edu/~kumar/cse6392/termpapers/Srikanth_paper.pdf *Zimmerman, James B. "Mobile Computing: Characteristics, Business Benefits, and Mobile Framework" April 2, 1999. https://web.archive.org/web/20111126105426/http://ac-support.europe.umuc.edu/~meinkej/inss690/zimmerman/INSS%20690%20CC%20-%20Mobile%20Computing.htm * Koudounas, Vasilis. Iqbal, Omar. "Mobile Computing: Past, Present, and Future" https://web.archive.org/web/20181110210750/http://www.doc.ic.ac.uk/~nd/surprise_96/journal/vol4/vk5/report.html