Abstract: Some implementations include identifying conflicts between multiple layers of supplementary content associated with a digital work (e.g., an electronic book). For individual conflicts between layers of supplementary content at one or more locations within the digital work, conflicts between layers may be resolved in favor of a higher priority layer. Upon resolution of the conflict, information associated with the higher priority layer for supplementing content at a particular location in the digital work may be determined. A visual identifier of the higher priority layer may be displayed along with content associated with the digital work at the particular location.

Abstract: Described herein are techniques for initiating item fulfillment at least partly in response to the users performing gestures on touchscreens of client devices. For instance, a user may operate a client device that renders content associated with an item offered by an offering service. The user may thereafter request to acquire the item by performing a gesture on a touchscreen of the client device. The offering service may receive the request and a representation of the gesture and, in response, may determine whether or not to initiate fulfillment of the item at least partly with reference to the received representation of the gesture.