Nicolaou will manage O2 Media's client sales team and will be responsible for developing mobile marketing solutions and working with client marketing directors in sectors including retail, FMCG and entertainment.
Nicolaou will replace Cluny Venables, O2 Media's head of client director, who has left the business to pursue other opportunities.
In addition, O2 Media is bolstering its agency sales team by hiring Alexandra Davies as agency sales manager, who joins from Channel 4’s future and digital media advertising team.
Nicolaou will report into O2 Media commercial director Gary Cole.
Cole said: "Our plans, roadmap and ambitions mean that we have an ongoing need for great people and this is largely being driven by client needs and education."
Nicolaou has long-stretching media agency background having worked at Mindshare, Initiative and Manning Gottlieb OMD across the automotive, FMCG, entertainment and finance sectors.
O2 Media launched in 2009 and last year rolled out a location based mobile advertising service for those who opt-in, which allows O2 customers to receive ads relevant to their location via SMS and MMS.
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