.mobi websites provide content which displays correctly and functionally on mobile devices such as palmtops, PDAs and mobile phones. dotMobi, the company which owns the .mobi top-level domain, has, since its launch, reserved about 650 city name domains. These are to become available to city governing bodies to promote relevant content for locals and tourists, from 20th August.

Local governments will have to make a proposal to dotMobi to request their domain name, outlining plans for marketing initiatives and a promise to have a .mobi standards-compliant website up and running within 60 days of registering the domain. The domains come with a price tag of €2,000 – the sum which the registrants are required to spend per year on promoting the domain name and website.

Helsinki.mobi, the first city .mobi domain to be trialled, has proved a success for the city. Representatives of the Finnish capital's investment promotion agency, Greater Helsinki Promotion, have championed the site, claiming that Helsinki.mobi has driven traffic and recognition to the city by providing a forum for both visitors and residents to express themselves. The launch of the site coincided with the Eurovision Song Contest in May 2007, but even since the initial success of the launch, the number of visitors to the site has remained steady.

dotMobi claims that 600,000 or so .mobi Domain Names have been registered, but some critics question the value of the sponsored top-level domain, arguing that Apple's new iPhone and other "smartphones" have the ability to resize web pages for use on mobile devices, ultimately making .mobi standards obsolete.