I don't use any exchange app, I am using only web browsers to access crypto exchanges. I feel that these apps aren't really secured, and the possibility of getting hacked is a lot higher when you use them, even if they are official apps. In addition, I have a computer and connection at home, so I don't need to use my phone necessarly in order to trade my coins.
I also prefer to use website instead of their Android or iOS application!
Even if you see the bitrex, they don't have their application on any platform I believe it will reduce the the any type of malicious attack on your exchange wallet.
So when the any project says they have application don't believe it. Wait for their input to make it bigger and explosive.