TOKYO/SEOUL -- South Korean e-commerce powerhouse Coupang, known as "South Korea's Amazon," is expanding rapidly in Japan on the back of its quick commerce or "Q-commerce" business in Tokyo.

Launched last year, Coupang is winning customers in Japan by promising to deliver purchases like foodstuffs and daily necessities in as little as 10 minutes, and within two hours at the most. The smartphone app for Coupang's ultrafast delivery service has been downloaded nearly 100,000 times.