A customer scans a QR code before shopping at the JD-running X-mart, a cashier-free supermarket, in north China's Tianjin, June 29, 2018. Operated by China's e-commerce giant JD.com, such supermarkets use technologies including the Internet of Things (IOT), artificial intelligence (AI) and biometrics to create an unmanned shopping experience. (Xinhua/Li Ran)

A staff member replenishes stocks at the JD-running X-mart, a cashier-free supermarket, in north China's Tianjin, June 29, 2018. Operated by China's e-commerce giant JD.com, such supermarkets use technologies including the Internet of Things (IOT), artificial intelligence (AI) and biometrics to create an unmanned shopping experience. (Xinhua/Li Ran)

Customers enter the JD-running X-mart, a cashier-free supermarket, in north China's Tianjin, June 29, 2018. Operated by China's e-commerce giant JD.com, such supermarkets use technologies including the Internet of Things (IOT), artificial intelligence (AI) and biometrics to create an unmanned shopping experience. (Xinhua/Li Ran)

A customer shops at the JD-running X-mart, a cashier-free supermarket, in north China's Tianjin, June 29, 2018. Operated by China's e-commerce giant JD.com, such supermarkets use technologies including the Internet of Things (IOT), artificial intelligence (AI) and biometrics to create an unmanned shopping experience. (Xinhua/Li Ran)