Cobinhood is a exchange that made without fee for every transaction. I believe cobinhood is pretty good but its not really popular like binance.
I believe it will be popular in the nearest future considering its free for transactions
I think it is free for now so maybe soon they need a fee for transaction because they want to be popular using that. When too many person always use that exchange, they haven't anything to do is to transact even it has some fee.
This is the reason they need to become a popular because of too many exchange, they want to be at the top before they put some transaction fee.