A nice discovery when using the the pre-release of Firefox OS.
NOKIA OFFLINE MAPS
Users can download Maps from Nokia using FireFox OS.
Installing FireFox simulator 0.7 (http://onsoftware.en.softonic.com/hands-on-withmozillas-firefox-os)
Then using Firefox install from local file.
Go the Simulator of FireFOX OS.
GO TO MAPS
Nokia Powered Maps then give you the option to download areas.
Save the Maps (between 4 & 18mb in testing)
Disconnect - Firefox 'work offline'
View the maps in Offline Mode
Note: This is still alpha - there will be bugs...
Please Report Bugs. https://github.com/mozilla/r2d2b2g/issues