Developed by Aliyun, Alibaba's cloud computing and AI subsidiary, the Alipay add-on relies on an AI algorithm trained on more than 150,000 pictures of muskmelons with differing levels of ripeness. Its accuracy is said to be above 90 percent.

Jiang Linbo, the owner of the melon store, said that classifying melons according to their sweetness helps to match the fruit to the customer's tastes. "I think agriculture can be high-end, and I always thought AI technology should be combined with agriculture," he said.