Originally Posted by
wco81
For European trips, without data roaming, you can't really use it anyways, though it does seem to cache some data.
I use the iPhone version without data roaming and it works just fine. You can't get maps, as you noted, but itinerary details will sync to the iPhone's TripIt app in advance, and you can also sync your iPhone's calendar from the TripIt calendar feed in advance so that plans show up on the iPhone calendar in the iPhone's time wherever you are.