With the mobile version of the Seoul Tour Card, you can purchase up to 10 cards at a time, and multiple people can use them together by adding them to the same app.

May I ask, if I purchase the digital version of the Seoul City Pass,
After downloading the ZhuanZhuan Card app, can one phone be linked to several ZhuanZhuan card numbers? (Can a whole family just use one phone to show their cards?)
Or does everyone need a cell phone?
If each person needs their own device, what should children do if they don't have a phone?
Thank you