There are various wireless alternates on Amazon.com one gadget gives iPhone readout. One person here has tried the FOBO system. As far as I know these stand-alone - they do not tie into your car's system. Not sure about Gen4, but the Gen2/3 TPMS sensors already read-out tire pressure and temperature. Toyota does not provide a screen to see this info, so you need OBD2 cord under your dash to a reader such as Techstream on a PC, or SCANGauge or other device. I am not sure if any of these provide a handy readout (although the Techstream is pretty handy if you want to have a laptop readout).