^ But these can't replace Flipkart. It's simply rocks. Moreover, their delivery people used to be superb. There was one guy in particular, who used to be there in our office every second day with someone's order, and we used to tell him-"Bhaiya, aap yahin reh jaao."
Most of the sites are online market places with different sellers/vendors selling different products. These sites work as interface between sellers and buyers, and thus once you've placed the order, the site forwards your order to the seller and most of the times the seller is responsible for the delivery and quality of the product. Though in between is the site's customer care/ policies that sometimes help get issues resolved, but again, these online marketplaces can't replace sites like Flipkart/HomeShop18, which most of the times stock the products and ship upon receiving the order. So, IMO, as of now, there's no alternative to FK (owing to it's awesome service and competitive prices-except a few exceptions).