Why is it doubling?
One of the things that will cause a coin to double or grow more in price is when people starts seeing the need for it and therefore investing in it. And also, people can only see the need for it when the project offers the chance. Now about this coin, it is obvious people started using it because it's being a long time I hear things about it. Also, owing to the nature of Ethereum network now, congestion etc, OMG now offers a better alternative to transfer USDT. Although TRC 20 chain can also be used to send USDT but not all exchanges supports it whereas all exchanges supports OMG chain.