As per official statements from Zebpay, reason for differences in market price and their prices :
Following quote is from their site's article[1]:
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Bitcoin price fluctuations on the bitcoin exchanges are driven by many factors. Below you will find the answers to the questions related to bitcoin price that is most often asked by our users:
What factors determine bitcoin prices?
Bitcoin prices depend on a lot of factors like international prices, market volatility, overall demand and supply in India and Zebpay’s internal stock position.
Why is there a difference in Indian price and international price?
At times, the Indian prices, both buy and sell prices, are 5-10 % higher than international market. This happens when there is high demand for bitcoins in India and sellers are not ready to sell cheap. Similarly, there are days when Indian prices, again both buy and sell prices, are lower than the international market.
It is important to note that, even in the international market at times, there is 5% gap between China and USA price and there are price gaps even within USA exchanges.
How do we get assured that Zebpay provides a fair price?
Zebpay works hard to ensure our users get best rates in India compared to other exchanges and trading platforms. We try to keep thin spreads and have implemented smart price algorithms which control and determine best prices based on both external and internal factors.
We understand the anxiety in the mind of a user when he finds bitcoin prices on Zebpay exchange different from international prices, but please be rest assured we do everything possible to keep prices as close to international markets as possible.
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[1]
http://support.zebpay.com/hc/en-us/articles/208927629-Why-there-is-a-difference-in-Indian-price-and-international-price-For unocoin their faq covers this point to some extent: [2]
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How do you determine bitcoin price in INR? And why are Unocoin prices occasionally different to other international exchanges?
At Unocoin, the price is calculated based on the bitcoin to USD exchange rate taken from various credible exchanges and its own orders. The main factors that influence its value are: The current USD to INR exchange, market fluctuations and most importantly the demand/supply of bitcoin. Every trading platform offers a buyer's price and a seller's price in order to meet (may not be the same across exchanges). In India we have seen this meeting price to be more than the international exchanges as the supply of bitcoin in India is comparatively limited. In a way every exchange is independent of each other and when there is a vast difference in prices between them there will always be speculators looking to make an arbitrage which consequently brings the rates more or less in sync with other exchanges. On some trading websites like Unocoin that is specific to a country (India), making a global arbitrage almost impossible. Hence it takes longer for its prices to sync with other international exchanges when there is a sudden spike or drop in bitcoin prices.
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[2]
https://www.unocoin.com/faq
