The bundled NaviMapper software runs on your PC and offers an easy way to download maps to your mobile device. Downloaded maps can be easily copied to your phone for navigation without a wireless connection.
To define a region to download map data for, simply click and drag. The right button allows you to pan around the map. A search box allows you to instantly jump to a particular area. In the screenshot, a search for New York centered the map there.
Download times can vary, at the highest zoom levels, it may take a while. The good thing is that NaviMapper does not clutter your device with thousands of map files - it creates a single database file - very neat indeed.
The mobile client was fast to pick up my location using GPS. Panning around the map was a smooth experience, showing the advantage of offline maps compared to online ones.
A separate feature allows you to track your movement. Information such as distance travelled and speed can be recorded and saved.
More information and download:
NaviMapper on xda-developers.com
Free to use, donations encouraged.