Troy will oversee Gamesys’ portfolio of brands, including Jackpotjoy, The Sun Bingo, CaesarsCasino.com and Virgin Games, which it acquired 12 months ago.
Troy, a former Barclaycard and Moneysupermarket.com marketer, joined O2 as head of marketing and consumer strategy in February last year, reporting to marketing and consumer director Nina Bibby.
During his tenure at O2, Troy contributed to the development of the brand’s 'Be More' advertising campaign, which rolled out last summer.
He will be replaced by Jonathan Earle, who returns to the UK business from his role as chief marketing officer for Telefónica in Slovakia to become head of customer strategy and development.
It comes amid a number of changes in the O2 marketing team. The firm has hired former Paddy Power and Sky marketer Danny Russell to the position of business intelligence business general manager, while Manchester City Football Club chief head of brand Ian Cafferky joins O2 in a newly-created marketing engagement role.
Troy said: "With the launch of the Virgin games brand in the US, it’s an exciting time to join Gamesys.com as it expands globally"
Gamesys was set up by UK-based games developer Noel Hayden in 2001, and launched Jackpotjoy – which has featured Barbara Windsor in its TV ads – the following year.
In 2012, it partnered with Facebook to roll out Bingo Friendzy, the social network’s first real-money gambling app.