Each content category has a nicely descriptive icon.  You can also select what sources you want loaded.  By checking only needed categories and map sources, you can increase the time it takes to finish drawing a map on the screen.

Next to the "g" icon are quick-access icons to the Home screen and Reader screen.  It would have been nice to have a Geode Info icon (a satellite maybe?), as the only way to get to the Geode Info application is to select View | Geode Info.

Map navigation is done by tap-and-drag to pan the screen and using the arrow icon next to the minus sign for zooming in on a specific area.  Tap the arrow icon then draw a box on the screen where you want to zoom into.  This is very handy, as you can actually zoom out almost 6,000 miles!  You can zoom in to slightly less than 1,000 feet.

If you only want to zoom in or out, you can also tap the plus or minus icons.  There is also a "slider" that lets you adjust the zoom control more quickly.  I put quotes around slider because it is not a true sliding control.  Tap and it zooms to that point.  This isn't very intuitive to me, and it's easy to accidentally zoom out so far that your map becomes a tiny speck.  I would rather have the slider removed or let it become a true slider control.  I would also like to see the Visor's up/down hardware buttons used to zoom in/out.

Rounding out the icons, the far right icon lets you collapse the toolbar so that you get basically a full-screen mode.