This summer Fox will begin testing technology that can update or swap ads that people see when they watch shows on demand, the network’s President of Sales Toby Byrne told buyers today. The goal is to have the service ready for next year. “A consumer can watch Fox on any device wherever they are, and your ad can be there too,” he said at the network’s upfront presentation at New York’s Beacon Theater. It was part of a joint presentation with Fox Broadcasting Chairman Kevin Reilly to underscore the company’s eagerness to work with new technology to help build ratings. “We will be No. 1 again next season,” Reilly vowed. The execs said that – unlike their broadcast and cable competitors — the network offers buyers “scale, youth, and influence.” Technology helps, they said: The network benefits from DVR time shifting, as well as streaming and VOD even though many of those viewers still aren’t fully included in Nielsen’s ratings. They added that Fox shows are especially popular with people on social networks including Facebook ad Twitter. “We dominate in the social space,“ Reilly said. “It indicates a certain level of engagement and that has value.”  The execs said that Fox has the youngest audience of the Big Four networks, and beat ad-supported cable networks which collectively offered 1,050 shows last year with only 4 in top 50. “None can deliver consistency, scale and breadth…the way Fox does,” Byrne says.