Over 10 million smartphones were shipped in September, IDC said in a statement.
"This decline could be attributed to incremental supplies witnessed during last weeks of September as the channels prepared for October's festive demand and online mega sales from major ecommerce players," it added.
Karthik J, Senior Market Analyst (Client Devices) at IDC India said owing to attractive discounts and offers during e-commerce sales, online shipments of smartphones grew 12.1 percent in October over the previous month.
According to Kiran Kumar, Research Manager (Client Devices) at IDC India, 4G-based smartphone shipments grew 25.9 percent month-on-month in October.
"4G-based smartphones accounted for more than half of smartphones shipped in October. This gain is mainly at the expense of 3G-enabled handsets as vendors are replacing their existing models with 4G-based smartphones while making consumers future proof," Kumar said.
IDC anticipates November to have maintained a similar shipment run-rate.