I am always annoyed by etherdelta's user interface. It is hard to use usually in mobile device and hard to scroll down especially when buying or selling. Unlike other trading sites have good UI. I can't stop using etherdelta because most of my tokens are only tradable in their slow site.
Apparently this is due to the fact that it is a decentralized market based on the smart contract. Several times I lost money when I had to cancel the order. It's awful. Here
https://idex.market/ is the same exchange, but easier.