Android, an operating system based on Linux kernel, has been widely applied in mobile and other devices, while its development on the function of wire telephones is still under exploration. This research goes through a comprehensive analysis and application of software and hardware, including Calling Identity Delivery(CID) circuits, Android system kernel driver, JNI invoking and message driving mechanism of Looper and Handler. Eventually it realizes a system to display caller information in the form of an Android APP by combining Android and CID. Tests have been conducted in the real system, and the experimental results prove Android's ability of receiving and processing messages from the wired telephone which contributes to its CID function. In summary, it enriches the function and application of Android.