City Pass is a ticket to public transport in Copenhagen delivered on your phone.
You can buy the City Pass ticket online this webpage: www.citypass.dk
Citypass tickets can also be bought at the ticket machines in terminal 3 just above the railway, and at the DSB ticket sales counter, also located in terminal 3. Please note that the machines only accept coins and all major credit cards, not notes.
You can also buy the tickets at the metro stations.