Analysts at Credit Suisse note that before Apple offered these EMI schemes to customers, iPhone sales were around 70,000-80,000 a month.
"From our channel checks we believe that iPhone sales are nearing 400,000 units per month in India - that is nearly 3% share of handset sales for a single top-end product in a market that has long been dominated by low-end feature phones," Credit Suisse's research analyst Sunil Tirumalai said.
Apple began its EMI scheme about four months ago, offering buyers the ability to make a partial payment on the iPhone 4 and 4S and then pay the rest of the amount in installments over 6 - 12 months with no interest.
"The 4-9% implicit discount coupled with the option of easy EMIs spread over 6-12 months became popular. Within a few months, our discussions with handset retailers indicated that iPhone sales went up 3-4x, forcing companies to respond," Tirumalai said.
It's widely rumored that Apple plans to release a low cost iPhone to better address emerging markets such as India.