Systems, apparatus and methods to supplement, combine, replace, verify and calibrate in-vehicle and in-device sensors and GNSS systems are presented. A mobile device and a vehicle navigation system share sensor and GNSS information to arrive at an improved navigation solution. For example, a navigation solution computed by a vehicle may rely on a sensor signal from a mobile device. Similarly, a navigation solution computed by a mobile device may use a sensor signal or a GNSS signal from a vehicle.