I signed up a couple of days ago on the Cobinhood (www.cobinhood.com) exchange and wired a small amount of ETH there to test whether it holds its promise of being fast and free (and secure), here my first experiences.
The registration is easy and fast and you are ready to go in no time. For larger amounts of course as usual you need to go through various authentication procedures.
The website still has some programmatic flaws (like graphical glitches) what I hope will be resolved soon. Also the balance in USD that is calculated is erroneous for me and the conversion rates for ETH and BTC in USD are somewhat strange. So all in all there are still a lot of problems that need to be dealt with.
On the other hand, the exchange is as promised fast and has no transaction costs. I believe that if the problems regarding usability are addressed, that this exchange could start a new area in crypto trading and will pose significant challenges to the traditional exchanges. For the moment I will keep my stack on the exchange small, but I hope at a certain point to be able to say that this is my go-to exchange.
One word: COBINHOOD also has an iOS app that I tried to test, but as it only showed Russian to me (what I unfortunately cannot read) I uninstalled it again.