A host system and methods are provided for engaging consumers to interact with at least a sub-set of digital content provided by a third-party client. The client also provides associated user engagement criteria and reward criteria. A user community platform may be defined for engagement, and a user interface and delivery network are established accordingly. The host system engages a user to interact with the user interface, either by proactively inviting user interaction or by receiving a request for interaction with the user interface. The host displays digital content to the user which is selected based on user criteria and the user engagement criteria. Completion of user engagement is confirmed based on the reward criteria, after which access is provided to a predetermined reward. User engagement data is collected by the host in accordance with the engagement criteria and the client is provided access to the user engagement data.