Core Viewpoint - The integration of Shanghai and Hong Kong's transportation cards marks a significant step towards seamless travel between the two regions, enhancing convenience for residents and promoting economic and cultural exchanges [3][5]. Group 1: Transportation Card Integration - Hong Kong's MTR has officially joined the national transportation card interoperability system, allowing Shanghai residents to use their "Transportation Union" marked cards for easy access to the MTR system without needing to purchase tickets or exchange currency [3]. - Hong Kong residents can also use their "Octopus" cards marked with "Transportation Union" in Shanghai's public transport systems, including buses and subways [3]. Group 2: Expansion of Interoperability - Since the launch of the national transportation card interoperability, 336 cities and over 1,700 counties have been integrated, covering various public transport modes and greatly facilitating cross-city travel [5]. - Following Macau's planned integration in December 2024, Hong Kong's inclusion will further enhance economic, cultural, and interpersonal exchanges between the regions [5]. Group 3: Local Transportation Innovations - Shanghai and Nantong have initiated interoperability for public transport codes, allowing residents to switch between cities seamlessly using existing apps without needing to download new ones [6]. - The "Suishanxing" app in Shanghai and the "Changxing Nantong" app have completed system integration, enabling users to scan codes for public transport in both cities [6]. - A pilot service for round trips between Shanghai and Nantong has been launched, enhancing the experience of regional transportation connectivity [6].