The same. When you install an app that uses GPS you have to give it permission to access your GPS on your phone. Some Navigation apps let you disable the GPS from the app and some don't. You can disable the GPS from all apps from your settings menu but I don't know why you would want to do that.

Keep in mind also that some GPS apps have a more comprehensive control settings that let you fine tune how you want the GPS to be used. On my Locus app when I'm navigating I have the option to leave the app and look at another app screen. If I do that the GPS is still on and tracking even when looking at another app screen. This allows me to just go back and check my location when I need to. ( now if I want to I can tell it not to track when I'm not looking at navigation, my choice. Usually though I want it to track me. )

Now if I wish to stop navigating and have the GPS stop I have to back out of the app using the back button on my screen. It will then ask me do I wish to exit navigation, at which point I press yes. Then the app tells me GPS is disabled and the app closes.

Google navigator is somewhat similar. You back out and it will ask you if you wish to exit navigation. When you say yes it then stops tracking with GPS. Like many folks I found out if you don't do this right the GPS will keep tracking and suck battery power. I have a real problem with the "Google Map" app. Sometimes when doing searches I have to press on a "google map" link to get a location of something I need to find. Once I'm done with the map if I don't back out the right way the map app will continue to run in the background...unaware. I found this out because when I use "Google Navigator" ( a separate app ) and close that out the google map app will sometimes come up which shows it was running in the background without my knowledge. Obviously the two apps are linked in some way which is quite annoying. When this happens I find the only way to get rid of the "google map app" running in the background is to reboot the phone. Now it doesn't do it every time I use "Google map" but sometimes if I don't close it out right it keeps running stealthily in the background, very annoying.