Current digital signage generally displays static contents with limited user interactivity. In this paper, we present a dynamic and interactive intelligent signage system (DIISS) with two main contributions. First, we propose a mechanism to generate dynamic contents using a dynamic playlist. Second, a gesture-based mechanism is introduced to enhance user interactivity with the users' smart phones. Furthermore, a Gesture Application Program Interface (GAPI) is implemented over an Android platform. For the purpose of evaluation, two applications have been developed: the Dynamic Intelligent Advertising System (DIAS) and the Interactive Signage Photo Gallery (ISPG).