I mostly use Bittrex for my trading. Although I ave opened accounts on Polinex, and Binnance as well. Some Altcoins are only offered on certain trading sites so it is good to open multiple accounts in my opinion so that you have access to the different altcoins that are out there. Bittrex works well on mobile as well. I have not been able to find the binnance app yet it isn't available to US customers that I can find, I tried downloading it the other day from there website and it said that it wasn't available in the US app store but it is available on the chineese app store but when I go to the chineese store it also says it isnt available. Hoping it comes tot he US app store soon so I give trading a shot on it. missed out on the surge the last few weeks on a coupel altcoins that arent available on bittrex.