How to draw from point A to point B like in navigation systems

It's going to be a very generic question.

By the way, I am trying to replicate this :

I created a web page that displays the lat/long information for whoever. It refreshes itself every X second.

I open my android, navigate to my web page, put the phone somewhere in the car and start driving. The idea is to capture my e开发者_如何学编程ntry/exit lines to see how good/bad my approach to an apex is.

I guess I need to understand how typical in car navigation systems work. They track you to the point. Any ideas?

I don't think GPS is going to be accurate enough for this.

Assuming you have a good fix on 5 or 6 satellites, your coordinates are typically going to be 15-30ft from your actual position. This is barely enough to determine which side of the road you're on, and probably won't help you.

Car navigation systems fake it to make it seem that they are far more accurate. They use information such as your current position, heading, and the road data it has to plot more precisely your location.

You can prove this easily. Take a car GPS system, and start walking away from the road. You will have to get a decent distance away from the road before it shows you aren't on it anymore. That is because the software is trying to compensate for the inaccuracy of the coordinates coming from the GPS.