China "T-Union" card can be used on buses and subways, trams and urban railways in almost all major cities, though it cannot be used in CR. Nevertheless, we recommend handling a "T-Unoin", or collecting one in the "wallet" on your iPhone or Apple watch, so that you can use public transportation conveniently. Other brands of cellphones or watches currently do not support cross-border or cross-regional traffic card services. Compared with the use of QR code, the card or NFC is faster in actual use. It is not necessary to open the QR code through the app, just finish the payment directly by swiping the card or iPhone and even your Apple watch, and it will not be affected by the quality of the mobile Internet. However, to use the card on your iPhone or Apple watch, you need to have a bank card that can pay in RMB, but the cards  issued by Shanghai are a different matter, they can recharge by bank cards issued by other countries, such as Visa Card or Master Card, so we recommend using the card issued by Shanghai.

At present, most Chinese people use QR codes or NFC on mobile phones for payment, so that there are few offline service outlets of traffic cards in some cities. If you need to get cards or recharge it, it is recommended to handle in the transportation hubs of some big cities. Most cards allow a maximum of ￥1000 for recharge and for cards issued in Hong Kong, the maximum at HK $3,000, which can be used for a period of time under normal circumstances. But these cards only recharge in the city where they are purchased or recharge by NFC.

Special attention should be paid to the fact that some city bus lines need to swipe the card respectively when getting on and getting off. If you forget to swipe the card when getting off, it is equivalent to not completing the settlement. Then this card may not be used in other cities, and you can only return to the city where you issued the card to pay the previous fee and unlock the card, or return to the city where you forgotten to swipe the card and swipe it again on any bus which need to swipe cards when get on and off. And you may also face to the additional fees or fines.

Remember the following icon, because you can only use it in the whole of China if your transportation card has it.