Gmap4 is a browser app (not a native app) that displays
high resolution topo maps for the USA plus all the standard Google map views.
Since it is a browser app (1) you do not have to download or install anything and (2) your browser has to be online.
To see the coordinates for your location touch Menu ==> My location
Check to make sure that the GPS in your phone is turned on.
Just open this link in the browser on your phone. Gmap4 works in almost all browsers on almost all devices.
Gmap4 default map:
http://www.mappingsupport.com/p/gmap4.php
To display the high resolution topo map, zoom in a bunch and then select "t4 Topo High".
One way to zoom in is by Menu ==> Search.
Full disclosure: I am the developer of Gmap4. This project is part of my way of 'paying it forward'. Translation: Gmap4 is free for non-commercial use.
The Gmap4 homepage has a FAQ, examples, quick start info (in the Help file) and more to quickly get you up to speed.
Gmap4 homepage:
http://www.mappingsupport.com/p/gmap4.html
In the current beta version Gmap4 starts to work more like a dedicated GPS with an improved 'My location' feature.
For beta info and a link please see:
http://www.mappingsupport.com/p/gmap4_beta.html
Joseph, the Gmap4 guy