Ocean
You say...
"No big deal I just dont know of any phraseology to differentiate and that indicates to the user that thay are in receipt of a APP service.
I remember saying something like " approach procedural service" cos I could not think of anything else, and being laughed at for weeks by the OJTI"
I thought that the use of your callsign "Bloggsville Approach" on initial contact was that very reason. However, if there is any doubt, e.g. the pilot still requests a radar service, your phrase "approach procedural service" is a very precise explanation and perfectly reasonable. I'm afraid that that OJTI needs to think things out a little more.