You can check the Debugging on Device
section in the online documentation regarding the different options available. As to Visual Studio specifically, please refer to the article on View logs in the AppBuilder extension for Visual Studio
. Generally to inspect the devices log, from the Show output from drop-down menu, select your device name. In the device log, you can track debugging events such as console messages.
The topic on Connect Apple iOS device in the AppBuilder extension for Visual Studio
may also be helpful.
Let me know if you have more questions.