But those alleged crimes could not have possibly helped by the app, as has been pointed out: you don't get to see individual officers' locations and it does not show areas with no police at all either, just police hotspots (and technically, most areas even in a dense city like Hong Kong are without immediate police presence most of the time, anyway).
But even if we played devil's advocate and took the allegations of criminal activity that abused the app at face value, and assumed Tim Cook is not free to share specifics as the information might be confidential, he could at least answer what local laws were allegedly violated by the app itself. Those laws certainly are not confidential information.