A timely progress monitoring is essential for the success of a large-scale construction project. It enables a site manager to properly prepare resources and make plans for the remaining part of the construction activities. Recently, mobile computing and image processing have been investigated as a means of automating progress monitoring. Mobile computing is advantageous in wireless data recording, retrieval, and transfer whereas image processing is able to analyze the site images to extract progress information. However, their potential applications in construction monitoring were rather separately studied; synergistic effect of both techniques has not yet been fully materialized. This paper presents an interactive mobile progress monitoring system to enhance the existing progress monitoring practices. The system utilizes the interactive feature of tablet computer to combine the strength of image processing and mobile computing. When a user selects an object on a construction site image in a mobile computing environment, the system provides a list of attributes for the object of interest. In this interactive environment, the user can easily match the object to the right attributes such as location, material type, and relation with other objects. This initial matching can then allow for automatic matching of other objects on the site to the right attributes of their own. The method can raise accuracy of image processing and significantly reduce the effort required to do the pre-processing for progress monitoring. A cable-stayed bridge construction project, a case study, is used to validate the proposed system.