What is mobile game?

A mobile game is a computer software game played on a mobile phone.
Mobile games may be played using the communications technologies present in the phone itself, such as by text message (SMS), multimedia message (MMS) or GPRS location identification. More common, however, are games that are downloaded to the mobile phone and played using a set of game technologies on the device.
Mobile games are usually downloaded via the mobile operator's radio network, but in some cases are also loaded into the mobile handsets when purchased, or via infrared connection, Bluetooth or memory card.
Mobile games are developed using technologies such as Macromedia's Flash Lite, DoCoMo's DoJa, Sun's J2ME (Java 2 Micro Edition, recently rebranded simply "Java ME"), Qualcomm's BREW (Binary Runtime for Wireless) or Infusio's ExEn (Execution Environment). Other platforms are also available, but not as common.

The different platforms
BREW is the more powerful technology, giving, as it does, complete control of the handset and complete access to its functionality. However this unchecked power could be dangerous, and for this reason BREW development process is tailored mainly towards recognised software vendors. While the BREW SDK (Software Development Kit) is freely available, running software on real mobile hardware (as opposed to the provided emulator) requires a digital signature which can only be generated with tools issued by a handful of parties, namely mobile content providers and Qualcomm themselves. Even then, the game will only work on test enabled devices. To be downloadable on regular phones the software must be checked, tested and given approval by Qualcomm via their TRUE BREW Testing programme.
Java (aka "J2ME" / "Java ME" / "Java 2 Micro Edition") runs atop a Virtual Machine (called the KVM) which allows reasonable, but not complete, access to the functionality of the underlying phone. This extra layer of software provides a solid barrier of protection which seeks to limit damage from erroneous or malicious software. It also allows Java software to move freely between different types of phone (and other mobile device) containing radically different electronic components, without modification. The price that is paid is a modest decrease in the potential speed of the game and the inability to utilise the entire functionality of a phone (as Java software can only do what this middle-man layer supports.)
Because of this extra security and compatibility, it is usually a quite simple process to write and distribute Java mobile applications (including games) to a wide range of phones. Usually all that is needed is a freely available JDK (Java Development Kit) for creating Java software itself, the accompanying Java ME tools (known as the Java Wireless Toolkit) for packaging and testing mobile software, and space on a web server (web site) to host the resulting application once it is ready for public release.

Common limitations of mobile games
Mobile games tend to be small in scope and often rely on good gameplay over flashy graphics, due to the lack of processing power of the client devices. One major problem for developers and publishers of mobile games is describing a game in such detail that it gives the customer enough information to make a purchasing decision. Currently, Mobile Games are mainly sold through Network Carriers / Operators portals and this means there are only a few lines of text and perhaps a screenshot of the game to excite the customer. Two strategies are followed by developers and publishers to combat this lack of purchasing information, firstly there is a reliance on powerful brands and licences that impart a suggestion of quality to the game such as Tomb Raider or Colin McRae and secondly there is the use of well known and established play patterns (game play mechanics that are instantly recognisable) such as Tetris, Space Invaders or Poker. Both these strategies are used to decrease the perceived level of risk that the customer feels when choosing a game to download from the carrier’s deck.
Recent innovations in mobile games include Singleplayer, Multiplayer and 3D graphics. Virtual love games belong to both of singleplayer and multiplayer games. Multiplayer games are quickly finding an audience, as developers take advantage of the ability to play against other people, a natural extension of the mobile phone’s connectivity.

Mobile games on i-mode
Since the start of i-Mode in February 1999, the global development of mobile games has been pioneered and is driven by i-Mode games. DoCoMo was the first carrier globally to introduce Java to mobile phones and for games on mobile phones. Japan also was the first country to introduce color screens and 3D graphics for mobile phones, which are necessary for expansion of the mobile game market beyond very simple games. i-Mode allows to overcome many of the limitations mentioned above.