If you created a group and you want to either leave it or give control of the group to another member, you can do so in the app or in the web version of GroupMe. Only the current owner of the group can change the group's owner – other group members don't have the ability to do this.
Sign in to your GroupMe account in a web browser or in the mobile app.
Make sure that the new owner is already a member of the group.
Select the group, click or tap the members list, select the new owner and choose Make Owner. Alternatively, select the group, click or tap Settings, select Change Owner and choose a new owner from the Group Participants list.
Keep in mind that once you've changed the group's owner, you can't undo it.