To date, using exchanges has entailed a high level of risk. Moving transactions offchain is one way of minimizing fees.

Binex: website here.
Aims to launch in late 2018, and will share 70% of trade commission with traders.

Bithumb
World's largest exchange by volume, as of 2017. Offers a $5 signup bonus.

Bluebelt
Gate.io: 10% of trading fees for the first year: click here.

Poloniex

You can also use Poloniex to make loans.

Uphold

Bitcoin exchanges: 21,000 monthly searches according to Google Adwords; CPC: 265 Yen.

My referral link!