I want to use smartphone instead of Genymotion emulator for debugging the apps that I develop. But I am not sure how safe it is to turn on Developer options. I am using HTC Desire 816g and I am not quite sure if doing this would affect the performance or any other aspect of my phone.
No problem arises when you switch on the developer option in your smart phone. It never affects the performance of the device. Since android is open source developer domain it just provides permissions which are useful when you develop application. Some for example USB debugging, bug report shortcut etc.