Tenn. Code Ann. § 55-4-138

In addition to the provisions of § 55-12-139 authorizing a person to display evidence of financial responsibility through the use of electronic devices, a person may also display evidence of vehicle registration in electronic format. The electronic images shall state that the vehicle is properly registered and that a certificate of registration has been issued to the owner or operator of the vehicle. For purposes of this section, acceptable electronic formats include display of electronic images on a cellular phone or any other type of portable electronic device. If a person displays the evidence in an electronic format pursuant to this section, the person is not consenting for law enforcement to access any other contents of the electronic device.