Cobinhood is a cryptocurrency exchange with no trading fees. Users can trade most of the major pairs, and a variety of other currencies. Cobinhood offers both both a centralized and a decentralized trading platform. In addition to their cryptocurrency exchange, Cobinhood also operates an ICO underwriting service, and they are releasing Zeux, which will be a crypto mobile payment and investment app.
The network is powered by the COB token.

Bithumb is the biggest Korean crypto exchange. It is a top 30 exchange by trading volume and it is one of the most significant blockchain companies in South Korea. In June, 2018, Bithumb was hacked and around $870,000 in bitcoin were stolen from customers.
Trading Fee: 0.15%
Withdrawal Fee: 0.001 BTC
Number of Tokens/Coins: 32

Poloniex is an established crypto to crypto exchange that is based in the United States. It offers a large selection of tokens to trade and has high liquidity. Poloniex was hacked in 2014, and lost more than 12% of their bitcoin supply. They have improved their security protocols since then. In February, 2018 Poloniex was acquired by Circle, one of the largest crypto payment providers.

Trading Fee: 0%-0.1% Maker and 0%-0.2% Taker
Deposit Fee: Varying Depending on blockchain fees
Withdrawal Fee: Varying Depending on blockchain fees
Number of Tokens/Coins: 97