Verdict. In India, WhatsApp call is definitely cheaper – A minute of WhatsApp call will cost you around 25 paise, while a normal mobile voice call will cost you anywhere between 50 paise to 1 rupee per minute depending on the plan that you use.o, you need to simply calculate, depending on the cost of the data pack as to how much it will cost you. On Idea Cellular, 1GB data pack costs around Rs. 250, so a 4 minute call on WhatsApp will cost you around one rupee.