Alibaba Group Holding said the destination ranking feature in its Amap mapping service has racked up 400 million users since being launched last month, as the tech giant doubles down on efforts to challenge rival delivery platform Meituan in local services.Amap Street Stars, launched on September 10 to provide artificial intelligence-based rankings for restaurants, hotels and tourist attractions, has so far been used by 400 million users, nearly half of Amap’s monthly active users, Alibaba said ...