I just started using Cobinhood the the younger, cooler brother of the free stock trading app Robinhood. I like it so far and they have some great incentives! There is a referral program, easy airdrops, and you can use fiat to purchase crypto, trade on their integrated exchange, and the transactions seem pretty cheap so far. If they follow in the way of Robinhood then i expect it to remain very cheap and efficient.
This app is available to anyone except people who live in Japan or New York (sorry guys).
Sign up with this referral and you will get a bonus just for joining!