Pembrooke, who takes up the role of group director of online and interactive operations, will oversee the radio broadcaster's portfolio of online brands and interactive services across analogue, DAB, radio and mobile, including Classic FM, Xfm and Capital 95.8. He will report directly to Fru Hazlitt, managing director of GCap London.
Prior to joining GCap, Pembrooke was director of product operations at Yahoo! Europe, where he developed and managed programme planning and delivery of new products, including Yahoo! Eurosports, Yahoo! Answers and the search giant's video player.
He has also worked at specialist consultants, including Portal Software and AT Kearney, where he provided CRM software for the internet and telecommunication's sector.
Hazlitt said: "The interactive and online development is critical for the future of GCap. Robin's talent and experience will help us deliver the breadth of vision that is required for this business."
Last month, a report in The Times said that the company had held talks with Emap about merging their respective radio businesses, which are the two largest in the UK.