adeb1

Hi all I had a Dvr cctv system of santa this year. Its a cnm primus 8ch. I am adding a ptz camera. Can anyone tell me if i need to buy a certain make? I have the rs port on the back and the dvr has ptz installed. But i also want to control the ptz from my i phone. i want one that has a decent spec but is compatable with my cnm stuff Thanks for any help Ade