It is hard to say which one is best but it is easy to get. I have my own cryptocurrency exchange which works great and it has a considerable number of users. Launching a crypto exchange has now become a way to establish yourself in the emerging cryptosphere. All you need is a cryptocurrency exchange developer who can give you a perfect platform. I got my exchange developed from Technoloader which provided me an entire team of developers who worked together and delivered a flawless exchange that works on the blockchain.
They also took care of the marketing and my exchange got a great start. If you also want to make a successful bid in this domain, then get your own crypto exchange software. You can also have a security token exchange platform which would garner more users in the future.
Try Delta Exchange.
It is one of the best exchanges for trading Bitcoin, Ethereum, Ripple, Stellar Lumen and other top cryptocurrencies with leverage. Bitcoin futures available on Delta Exchange offer upto 100x leverage. Max leverage for every futures contract can be found under the contract details section on the trading terminal. Settlement currency for the margin used and quoting currency for any contract can also be found on the contract details page. You can also refer to bitcoin daily future, Ether Futures guide, Ripple futures guide and other futures guides listed in the footer to find details on the contracts available for trading.