First, make sure your Planapple trip has start and end dates set. This how Planapple knows what items from TripIt it should import. (You can set your trip dates by clicking "Edit Trip" under your trip's name on the top left of the Planapple trip page.)
Then, get your calendar feed link from TripIt:
- In your TripIt settings, go to the Publishing Your Data section
- Under "For yourself ... Calendar Feed", make sure that both "Include detailed items in your calendar feed" and "Automatically adjust time zones in your calendar feed" are checked.
- Click the Subscribe link next to "Calendar Feed". Then in the Add to Calendar dialog, click "Subscribe to calendar feed".
- Copy the calendar feed link (starting with "https://www.tripit.com..." and ending with ".ics")
- Click "Import from TripIt" under the calendar on the right side of the page.
- Paste in the calendar feed link you copied from TripIt, and click "OK".
After the initial import, note that it can take up to 24 hours for later changes in TripIt itineraries to be updated in your Planapple itinerary. (TripIt doesn't update its calendar feeds immediately.)
If imported event times or dates seem to be incorrect, you may need to adjust timezones for the items.