With the MT4 app for the phone (watch a video to install MT4 on Phone) you can control your trades in your trading account; make, close, edit, and cancel trades.
With the MT4 app, you are not able to turn off your auto trading, which is essential to stop the expert advisors from placing more trades. To do this you need to access the VPS so you can get to the Auto Trade button at the top of the MT4 software. To do this you will need a computer, have a person that can access your VPS from their computer or use the Remote Desktop app to access your VPS from your phone. Here is the video on how to use the Remote Desktop Client.