Adding people to your trip is currently only possible on Mapify's website. To do the following, please visit https://mapify.travel and log in with your Mapify account.
To add people to your trip on Mapify, open your trip by finding it on your personal profile and click the trip edit button in the right sidebar. You will find a section to add travelers. Just type in the name of the user you would like to add to this trip. Attention: They must have created their own Mapify account before you can add them to a trip.