Navigation system having mileage mechanism and method of operation thereof

1. A method of a device, comprising:

determining, by a processor, a previous location reading associated with a route and a previous heading associated with the previous location reading;

determining, by the processor, a subtotal mileage associated with the previous location reading;

receiving, by the processor, a current location reading associated with the route and a current heading associated with the current location reading;

calculating, by the processor, an incremental mileage based on the current location reading and the previous location reading;

calculating, by the processor, a total mileage based on the subtotal mileage and the incremental mileage for display at a display device;

calculating, by the processor, a change in heading between the previous heading and the current heading;

determining, by the processor, that the change in heading meets a threshold heading criteria;

responsive to determining that the change in heading meets a threshold heading criteria,

updating, by the processor, the subtotal mileage with the total mileage; and

updating, by the processor, the previous heading associated with the previous location reading with the current heading.

2. The method of claim 1 , wherein the device is integrated with a vehicle.

3. The method of claim 1 , wherein the threshold heading criteria changes based on characteristics of a geographical location.

4. The method of claim 1 , further comprising: initializing the subtotal mileage to a predetermined value.

5. The method of claim 1 , further comprising: generating and displaying a graphical representation of the route at an output unit coupled to the processor.

6. The method of claim 5 , wherein the graphical representation of the route includes display of a street map.

7. The method of claim 1 , further comprising: providing turn guidance to navigate the route.