In this paper, we describe a tactile feedback for a button GUI activated by a tap gesture on mobile touch devices. We implemented a new HW platform based on a film-type actuator to obtain a large range of tactile expression. From the analysis of touch interaction and user tests, we designed tactile feedback patterns and evaluated them. Two experimental results showed rapid response time, short falling time, and patterns responding to 'Touch' and 'Release' user gestures are important elements for simulation of the feeling of physical button clicking.