Senior citizens learn about a smart door lock at the 2024 Shenzhen International Intelligent Elderly Care Industry Expo in Shenzhen, south China's Guangdong Province, Oct. 27, 2024. A total of 203 exhibitors from home and abroad have brought more than 1,000 products and technologies for elderly care to the expo, which was held from Oct. 25 to 27 in Shenzhen.