Kalpana Kalpana (Editor)


Updated on
Share on FacebookTweet on TwitterShare on LinkedInShare on Reddit
Introduced  2005
Registry  Afilias
Status  Approved
TLD type  Sponsored top-level domain
Sponsor  Nokia / Vodafone / Microsoft / Afilias
Intended use  Sites intended for mobile device use

The domain name mobi is a top-level domain (TLD) in the Domain Name System of the Internet. Its name is derived from the adjective mobile, indicating it is used by mobile devices for accessing Internet resources via the Mobile Web.


The domain was approved by ICANN on 11 July 2005, and is managed by the mTLD global registry. It was originally financially backed and sponsored by Google, Microsoft, Nokia, Samsung, Ericsson, Vodafone, T-Mobile, Telefónica Móviles, Telecom Italia Mobile, Orascom Telecom, GSM Association, Hutchison Whampoa, Syniverse Technologies, and Visa, with an executive from each company serving on mTLD's board of directors.

In February 2010, Afilias acquired mTLD Top-Level Domain Ltd. (known publicly as "dotMobi").


DotMobi domain names have been available for registration by the public since 26 September 2006.

dotMobi engaged with the W3C Mobile Web Initiative (MWI) to help formulate the MWI Best Practices for mobile content. The practices outlined a number of ways to achieve good user experiences on mobile Web-enabled devices, and recognized several methods of implementing these practices.

mTLD has released a free testing tool called Ready.mobi (see mobiForge) to analyze the mobile readiness of websites. It does a free page analysis and gives a .mobi Ready score from 1 to 5. This report tests the mobile-readiness of the site using dotMobi's recommended best practices.

dotMobi does not itself mandate any particular technology, but does require that .mobi sites produce user experiences consistent with their guidelines and specifically optimized for mobile phones.

The domain has been the target of criticism due to allegedly breaking the principles of device independence. Providing content tailored to particular devices can be done by other means than a specific TLD, such as using hostnames within an existing domain, HTTP content negotiation, cascading style sheets, or other forms of adaptation.

Similar services

There are technical solutions that provide similar benefits as mobi: compressing/downsampling proxy servers and microbrowsers, like Opera Mobile, which can tailor any website to small display (using Small Screen Rendering technique). However, these browsers must still download an entire page (with graphics and other related files) which, if not optimized for mobile phones, can be time-consuming and expensive to download. To improve the latter issue, the two adaptation techniques can be used together. This is the idea behind proxy-based microbrowsers like Opera Mini that download the optimized and compressed version of web pages through dedicated proxy servers. However, web pages viewed on a mobile via a proxy-based microbrowser are rarely specifically designed for a mobile phone, so it is left up to the proxy server and browser to decide what to compress, what to display, and how to display it, which, unlike the .mobi version of the site, may not necessarily be how the web page owner intends for the mobile audience.

There are also specialized content adaptation solutions, that typically operate on a server, where they employ specialized adaptation techniques to provide optimized representations of Web sites to mobile devices regardless of what browser they use. However, .mobi replaces the intermediary step with the specific adaptation of content for viewing on a mobile phone.

The W3C is also developing new authoring languages, such as DIAL (the Device Independent Authoring Language), which aid authors in creating Web sites that can be used on the huge variety of mobile devices available today. Some adaptation solutions already support the use of DIAL and similar languages in creating sites that can be used with .mobi domain names. Other open source initiatives include WURFL which addresses the problem with a large database of browser identification strings.


All mobi sites must be optimized for viewing on a mobile phone, providing the major advantage of the domain, from the users' perspective, of compatible content. Websites may be optimized for the special capabilities and restrictions of mobile devices, such as smaller screens, device form/size, device input/output options, existence of embedded sensors (acceleration, location, touch, etc.), as well as human factors such as expectations of immediacy of results, context awareness under a shortened attention span (compared to non-mobile device use of the Internet). Although other top-level domains can technically employ the same optimizations for mobile phones, in practice, only a fraction of them do, thus necessitating content adaptation solutions. These retrofit the content to target devices independent from the original process of creating the site. On the other hand, dotMobi promotes creating two separate device-dependent World Wide Webs, one desktop-based and the other mobile-based, and thus risks producing redundant content. From a content provider perspective, having to maintain two separate websites also represents more work.

Tim Berners-Lee of the World Wide Web Consortium, claims that dotMobi breaks the device independence of the web:

It is fundamentally useful to be able to quote the URI for some information and then look up that URI in an entirely different context. For example, I may want to look up a restaurant on my laptop, bookmark it, and then, when I only have my phone, check the bookmark to have a look at the evening menu. Or, my travel agent may send me a pointer to my itinerary for a business trip. I may view the itinerary from my office on a large screen and want to see the map, or I may view it at the airport from my phone when all I want is the gate number.

Critics pointed out that "mobi" is an unfortunate choice for mobile phone text entry interfaces, requiring nine or ten keystrokes in many common setups, compared to seven for "com", or what could have only been three if "wap" was used. There is a possibility that mobile phone manufacturers may in the future default their mobile internet browsers to .mobi or that predictive-text input features will reduce this to one keystroke, either of which would effectively eliminate this issue.

Currently, much web development is changing to a mobile first, responsive design methodology, reducing the need for separate mobile sites and restricting the market for .mobi domain names.

Allocation of premium names

mTLD has compiled a list of approximately 5,700 commonly used words and phrases that have been set aside for equitable allocation other than in the traditional first-come, first-served system. This was designed to 1) create a more level playing field in the allocation of these names, 2) increase the likelihood that these domain names will more promptly provide the mobile community with new features and services, and 3) preserve the stability and security of registry operations. mTLD will be allocating these premium names via auction and Request for Proposal (RFP) processes on a quarterly basis through 2008. The process was approved by ICANN with input from mTLD's Policy Advisory Board and WIPO. Disputes that arise over .mobi domain names can be filed and administered by the National Arbitration Forum. Disputes are decided by one of 147 experts on the National Arbitration Forum's intellectual property panel.

On 13 September 2007, dotMobi announced the auction of 100 premium .mobi domains via Sedo to commemorate their 1-year anniversary since public launch.

dotMobi has sold hundreds of domain names through the auction process, but it has not been without controversy. In one auction, a dotMobi website sold for $616,000. The auction was voided due to technical problems at Sedo. Also, none of the top 25 most expensive domains sold at the first auction met their compliance deadlines to have active web sites.

Reserved names

In connection with the roll-out of the .mobi top level domain, dotMobi has reserved names as per its contract with ICANN. These terms include dotMobi terms, other TLDs, emergency numbers and geographic names. The first geographic .mobi domain to be released was Helsinki.mobi

Domain aftermarket

A dozen of domain name sales in the mobi TLD have fetched prices in the hundred-thousand-dollar range, including Music.mobi, Games.mobi, Flowers.mobi, Poker.mobi, Ringtones.mobi, Casino.mobi, Sportsbook.mobi, News.mobi, Porn.mobi, Hosting.mobi, Sports.mobi, and Fun.mobi. Overall over 3,000 .mobi domain names changed hands publicly since its inception.


.mobi Wikipedia