Flipkart & Amazon have taken several communication and tech enhancement measures to ensure that the GST reductions are passed on to customers.
The flagship sales come just a day after the new GST reforms take effect, with lower rates on big-ticket appliances expected to fuel higher festive spending.
AirPods 2nd-generation has dropped to lowest-ever price.
Apple iPad will be available under Rs 20,000 during upcoming Big Billion Days sale.
While rival Amazon had initially revealed that its competing sale event, the Great Indian Festival (GIF), will begin from October 10, it has changed the date to start at the same time as Flipkart's BBD.