I think flipkart is the Indias number one shopping site. If I taking about the customer service of flipkart is very good. They try to resolve all issues within 24 hours. Product quality its depending on the merchant they have with them. However flipkart also assured lots of products. Which are checked by flipkart itself.
Flipkart has a very good delivery time. Till now whenever I ordered I received it before the expected delivery time.
The Web site and the mobile app are very organized and easy to use and find wanted products very easily.
Flipkart is also very reliable as they have 30 days return policy which means if you dont like the product you can return any time within 30 days.