If your friend HAS already received their Mobile Ticket in their App, your Mobile Ticket and E-ticketare no longer valid. If your friend forgets their phone, you can always revoke the ticket by going to My Events in the AXS App, then selecting the event and the tickets you want to revoke.
If your friend has HAS NOT received their Mobile Ticket in their App, you can revoke the shared ticket and your printed eTickets will remain valid.