Exterior means, you can use this to clean the tires, wheels, engine bay etc. But you may need to follow the dilution ration as suggested by the manufacturer. Certain APCs (Some manufacturers call their APCs as something else for eg: Car Cleaning Products
, you can see here the gtechniq's APC is called as 'Universal Cleaner' but they are also APCs, but they are little more concentrated than Meg APC, costlier also :-) )
Be careful, when you use Waxpol in the dashboards, as they tend to give lots of reflection due to the glossy look. I prefer to use some synthetic products instead of wax to protect the dashboard.