There are a number of SMS service providers in India who provide Magento SMS API and also other SMS APIs for  e-commerce platformS like Opencart, Woo-commerce etc. I am running two e-commerce platformS with different segments clothing and grocery and I experienced the importance of SMS API for my e-commerce platform. After enabling SMS API in my magento platform I experienced better sales and customer relationship. I am using MSG91's SMS Gateway API from last 1 year and I must they have built an amazing Two factor Authentication platform called Send OTP. Please Share your experience with Magento SMS API