1. An apparatus comprising a first computing device including a computer processor and a computer memory operatively coupled to the computer processor, the computer memory having disposed within it computer program instructions that, when executed by the computer processor, cause the apparatus to carry out the steps of: identifying a candidate application to be installed on the first computing device; identifying a trusted user that a user of the first computing device has identified and indicated as being trusted; receiving from a second computing device, an indication of installation activity of said candidate application by said trusted user on said second computing device; and determining whether to install the candidate application on the first computing device in dependence upon the indication of installation activity.