Abstract: We present CheatSheet, a novel contextual interactive memory aid that helps users track their learning progress and refind information when working with complex web applications. Unlike most refinding systems that rely on background monitoring of search sessions or browsing histories to automatically suggest content to users, our approach actively engages users in assessing and curating helpful content for later use. Users create application-specific notes using CheatSheet that contain the visual state of the application overlaid with any text or diagram annotations. Users can also extract snippets of relevant help and tips from other web resources (or other users) and link them to their application-specific CheatSheet. Instead of having to remember or scour through previous notes, bookmarks, or folders, CheatSheet automatically retrieves the recently added notes within the application's user interface. We discuss findings from formative interviews that we used to derive a set of design goals for designing an interactive memory aid, present the design and implementation of CheatSheet, and report on an observational user study that sheds light on the range of users' note-taking and refinding strategies that CheatSheet was able to successfully support.