Are you asking to know where you are or to show someone else where you are?

I have an iPhone and use Pocket Earth to show me where I am without having to have internet connectivity. It will also display detailed maps that you have to download (for free) before hand. The app is a few bucks.

To show others where I am, I use TrackMyTour. You can set waypoints without internet connectivity but have to post to the internet for others to see.