Here's how an App is NOT protection. LEO busts Hubei House of Relaxation. LEO goes through their phone, finds your handle on whatever app you used. LEO subpoenas AppCo for the info associated with your account handle. AppCo says sure, we like doing business in the USA, and hands over IP address of your phone, or your disposable email with them, or if you used your real telephone number, your real telephone number.
If you're smart, you used one of those overseas email services, but how many guys use a disposable gmail from Google? LEO contacts Google, Google gives up the IP address from which you check your gmail. LEO knocks on the front door and says "Hello, Mr. Kraft."
There are ways around this, but you'd better know exactly what you are doing.
LEO takes down terrorists, drug gangs, mobsters and spies. You are not as good as they are.