A virtual content server and method are provided for giving virtual content providers an opportunity to provide their virtual content, such as an advertisement, to a mobile device of a user who has achieved or otherwise satisfied one or more predetermined conditions in, or interacted in a certain way with, one or more mobile apps on the mobile device. When a certain condition is satisfied in a mobile app of the mobile device, a device identifier of the mobile device is sent to the virtual content server and stored in a previously-generated recipient list of users in a recipient list database. When a virtual content request including the device identifier is later received from the mobile device, the virtual content server retrieves as at least part of a plurality of virtual content candidates virtual content previously associated with recipient list(s) for which the device identifier has been stored in the recipient list database. Then, one or more of the virtual content candidates are selected and sent to the mobile device to be displayed.