It has brought marketing director Paul Hamburger back into his old role after a three-and-a-half year absence, during which time he worked for T-Mobile as senior director for end-user marketing.
Hamburger, who will also be given a place on the board, takes over from director of marketing Julian Neil, who will stay with the phone chain in a new role within the 20-strong marketing team.
Hamburger said he had decided to rejoin Phones4U because the time was right to challenge Carphone Warehouse's high-street dominance. "We want to overtake them in all measures and now it's very achievable," he said.
Phones4U's recent campaign, featuring voiceovers by Paul Merton, has been hailed as successful at bringing in new customers. Hamburger said plans for a further campaign with Merton had not yet been finalised, but any future activity would continue to feature celebrities.