1. A method comprising: by one or more computing devices, collecting a plurality of information items of a plurality of types relevant to a user; ranking the plurality of information items based on their respective degrees of relevance to the user; constructing an information feed that includes the plurality of information items in an order of their respective ranks; and sending the information feed to a user device associated with the user for presentation of the plurality of information items to the user in the order of their respective ranks.