1. Binance
New cryptocurrency exchange platform with 0.1% fees and supports many cryptocurrencies.
2. HitBTC
Another platform that tries to make trading as cheap as possible and supports many cryptocurrencies.
3. Kucoin
Also a new platform with 0.1% fees plus you get a portion of all the trading fees (Kucoin Bonus) on the network depending on the amount of Kucoin Shares (KCS) you have. It doesn't support a lot of cryptocurrencies though.
4. Bittrex
A very powerful platform for cryptocurrency exchange with a great API for developers and supports a lot of cryptocurrencies.
5. Cobinhood
Cobinhood is zero fee exchange platform but supports only a few coins.