[willysp]

I think Garmin XT is the best GPS package for use in phones - and in short, casual situations where you don't have phone coverage.

I would NEVER depend on XT in my phone for longer periods out of phone range, where getting lost would be more serious. Phones are fragile, etc, etc. In those situations, I always use a handheld Garmin unit, and take a lot of rechargeable AA batteries.