Is the Anne Pro android app secure?

I've got my Anne Pro a couple of days ago and I'm really happy with it. I'm not experiencing any of the known problems (rgb, battery or rattly stabilizers). I'd like to do some configuration to the keyboard but my main desktop runs windows 7 and I'm not sure about installing an android app from outside the Play Store to my phone. Anyone has tested the application for security issues? I know that any app could have malware but China has been a frequent source for this kind of apps.