Not very reliably. AFAIK, the geographic resolution on phones GPS would not hold up to scrutiny if you were driving within 10-20% of the speed limit.

I'm not talking about real speeding, I'm talking about driving 70-75 in a 65 because that's what traffic is doing. A week later I get a ticket in the mail because some zealous law enforcement agency subpoenaed a bunch of records from automatic.com. Maybe I'm being paranoid but it doesn't seem to fall far outside the realm of possibility these days.