Thanks for your replies. In XDK, the Plugin Management drop down has the following permissions listed. See below:
Cordova-Plugin-File:
android.permission.WRITE_EXTERNAL_STORAGE
Cordova-Plugin-httpd:
android.permission.INTERNET
android.permission.ACCESS_NETWORK_STATE
Cordova-Plugin-ad-admob-sdk:
android.permission.ACCESS_COARSE_LOCATION
android.permission.INTERNET
android.permission.ACCESS_NETWORK_STATE
My app only has banner ads so I can understand asking permissions to 'access location' so that the ads are relevant to the user but the others I do not see as being applicable. Is it possible to remove the 'Cordova-Plugin-File' and 'Cordova-Plugin-httpd' plug-ins or do they have some other use that I am not aware of?