Tap the '+' icon in the bottom navigation to create a group OR tapping the '+' in the top right hand corner of the groups screen in the app.
Restrictions: Private and managed groups are only available on Pro.
Go to the group you want to invite people to and tap the info icon in the bottom floating menu. The number of people you can invite or have as admins will vary depending on the subscription you're on.
Admins: If you're the group owner and you have the feature enabled you will be able to add admins / set active group members as admins. Free groups don't have admin controls (as you can only create public groups).
Members: Create invites via Instagram, WhatsApp, Facebook, Twitter, copy a link, share a QR code or select other share sources.
Admin groups are restricted to Pro plans. Go to the group you want to manage and tap the info icon in the bottom floating menu. The number of people you can invite or have assign as admins varies depending on the subscription you're on. Here you will see join requests there and have the option to approve or decline requests.
Real-time collaboration within groups is only available on Pro plans. Collaboration allows members to share and see changes and edits and realtime within the group.