hi! to all,

I searched the forum: index & glossary
but couldn't find answer to these questions:

what means JCV & G2S?

what is the use of the base map?
I made tries with and without ... didn't notice any difference

do I need all this stuff: JCV / G2S / base map
to run Garmin XT on a WinMo 6.5 phone (HTC HD2)

thank you for your help & hints
Laurent