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

CEX.io is a British company that changed its focus from mining into becoming a cryptocurrency exchange. CEX has made an effort to add many coins, and boasts of fill-or-kill (FOK) orders that allow for some of the industry’s fastest trading, but it has a poor record on privacy and transparency that should give pause to traders.
The exchange’s fill-or-kill (FOK) orders are very fast, but come at a steep 7% fee. The mobile application is easy to use, and there is also an API integration. CEX is a regulated exchange that complies with all KYC and ALM laws, so they are able to accommodate several funding options, including credit cards and bank transfers.
The majority of CEX.io’s trading volume is done with bitcoin, and although they have made an effort to add more coins, this exchange simply does not have the trading options that others do. The low trading volume of other major coins provides limited liquidity for most traders.
Trading fees vary depending on trading volume between 0.16%-0.25%.Bank transfers are free and withdrawal fees are lower compared to their competitors, but transfers can take up to 20 days.
Although CEX.io is easy to use and allows for very fast crypto purchases, it has high fees, delayed withdrawal times, and a poor record on privacy/transparency.

Kyber is a decentralized network and exchange that is focused on providing liquidity. Kyber enables token transactions between platforms and aims to make these exchanges of value easier, by connecting different ecosystems and applications. Kyber users can exchange tokens with greater liquidity because the network maintains a reserve of all tokens. Transactions are very fast and are processed via smart contracts that have a derivative functionality where users can hedge currencies to lower risk. Kyber can also be used make payments to anyone, in any token, across any platform. The network is powered by the Kyber token (KNC) that was released in an ICO that raised almost $49 million.