We demonstrate a seamless vertical handoff solution, called Universal Seamless Handoff Architecture (USHA). USHA is simple and requires minimal modification to the current Internet infrastructure. Therefore, it is instantly ready for real-world deployment. In this demonstration, we present USHA in two scenarios. Using video streaming applications, we demonstrate that USHA is able to successfully maintain the application connectivity and achieve almost zero delay during a vertical handoff. Moreover, we present a vertical handoff detection technique based on the end-to-end link capacity monitoring. The ongoing work of this study is to improve the accuracy of the handoff detection and to enhance application QoS support for vertical handoffs given the accurate handoff detection is provided.