Abstract: In various implementations, a first computing device (such as cloud-based server) transmits instructions to a second computing device (such as a notebook computer, tablet computer, or smartphone). The instructions are usable by the second computing device to render at least a first portion of the document on a display. The first computing device receives an asset identifier and a user comment from the second computing device. The asset identifier uniquely identifies a discrete subset of user content within the document (such as particular paragraph, a table, or a cell within a table). The first computing device stores the comment (e.g., in a cloud-based database) in a data entity that is separate from a data entity in which the user content identified by the asset identifier is stored and associates the comment with the asset using the asset identifier.