Lloyd James Group beat off competition from Swetenhams and Uni-Marketing to win the work.
Lloyd James's first task will be to launch the database, which will take the form of a two-stage email and SMS campaign involving a competition to win a Nokia 5510 mobile phone.
FoneTastic allows users to send free SMS messages, operator logos, ringtones and other content from PCs to mobiles.
The database is made up of 180,000 opted-in registrations from Fonetastic.com and the Fonetastic SMS network.
Lynne Stevens, managing director of Lloyd James, said: "The key to the FoneTastic database is its flexibility -- its structure will allow advertisers to use their preferred channel or a multiplatform marketing campaign to reach these individuals."
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