Which factors decide with which name I appear in the group member list?

A group's list of members will ve shown on the main page of that group for all openCards members. As with every part of openCards you may freely decide if only your user name is to be shown or if you wish for your first and family name to be visible. In your "Profile" you can decide, which details of your profile should be visible to whom. Something like your Christian name or telephone number can be visible to "nobody", only to your contacts ("my contacts") or to "everybody". Only your user name is always visible to everybody.

According to the information and settings given your name may or may not be shown in a group's list members. If you haven't "cleared" your name for everybody (or your contacts) only your user name will be displayed.