Its easily 10-15 years before technology like this would be perfected for realistic everyday use.

From the sound of it the phone detects cellular changes and not the actual virus or pathogen itself. Changes like that usually take a number of months to set in post infection; it might have an application in the developing world where the ability to test thousands cheaply is needed versus no testing at all, but porn needs a much more precise test.

PCR-DNA testing remains the most precise out there; its been that way for two decades and will remain that way for decades to come. No other testing method has a detection window even close to the initial date of infection like PCR.