Though I access with Proxy when using a WiFi in public places, I never thought it will mean the same thing when using it with apps because I currently run an MT4 and MT5 apps on my phones. If there are risks of such nature, then why have them in apps because I still have a payment processor that has an app which I use.
Actually using MT4 and MT5 apps on phones are quite safe rather than using a WiFi in public places, which is a big threat. It is tough to hack on smartphone and it happens very rare. But beware of using WiFi at public pace. If it is disclosed that you trade through a WiFi in public places, then there is a full chance of stealing your personal information. Always use password to Wifi and change the network type to private. It will keep you much more secure.