Amazon has launched a Hindi version of its mobile website and smartphone app in a bid to attract millions of new customers in India.
A KPMG-Google study showed the number of Hindi internet users is likely to top English-speaking users by 2021.
Amazon's move will boost competition with Flipkart, India's biggest online retailer, which is owned by Walmart.
The pair are engaged in a battle for customers in the country's $33bn (£26.7bn) e-commerce market.