AllofUs, which was co-founded by the outgoing D&AD president, Simon Sankarayya, will retain its name and sit within the McCann London building.
The agency was launched in 2003 and is led by the founders Nick Cristea, the design director; Orlando Mathias, the director of research and development; Phil Gerrard, the business director; and Sankarayya, the art director.
AllofUs will work with all of the McCann Worldgroup agencies, but its team will initially focus on projects with McCann UK businesses: McCann London, led by the chief executive, Chris Macdonald, MRM London and Momentum London.
The team of 30 staff will also work with the McCann New York and London chief creative officer, Linus Karlsson, and Matias Palm-Jensen, McCann Erickson’s chief innovation officer for Europe.
AllofUs’ clients include BSkyB, Telegraph Media Group, the Victoria and Al-bert Museum, Westfield and Xbox.
Nick Brien, the chief executive of McCann Worldgroup, said: "The creative uses of technology and user-experience design have become two increasingly crucial components for any brand agency looking to compete in this new world. This acquisition will bring to bear AllofUs’ expertise and experience on a more global and integrated scale."