A liquid crystal device with switchable dynamic and memory modes was investigated and developed. The proposed device reveals the splay, $pi$-twist, and bend states via selective switching among them. In the dynamic mode, the device is operated in the bend state, which exhibits a wide viewing-angle and a fast-response-time due to its self-compensated bend structure and flow-accelerated fast response time, respectively. In the memory mode, the permanent memory characteristics in the splay and $pi$-twist sates are obtained, respectively. The switching mechanisms of the tristate device are also proposed.