Cash are sometimes not accepted, or most shops do not have money for exchange.
Credit cards are rarely accepted, except for Starbucks and hotels. That said, credit cards may be useful for paying a deposit when checking in at hotels.
As of 2023, it is possible to use international credit card to make transactions uing Alipay or WeChat pay. Please follow the instructions in the linked URL, and download and install the international version of AliPay or WeChat app on your smart phone. When you create a new WeChat account, you may need help of someone from China (see below).
N.B. I could link a foreign credit card to an Alipay account from outside China.
To use the free WiFi at the Nanjing (and Shanghai) airport, you need to find a ticket machine for registration (or go to Starbucks). Public WiFi is not ubiquitous in the city.
If you use G-mail, set up a mail-forwarding, another e-mail account or VPN before coming to China.
The SIM card for travelers (which can go across the Great Firewall) is not sold in Nanjing. If you want to use your mobile, purchase a SIM card for travelers before coming to China. Such cards can cross the Great Firewall, but will become invalid after several days.
Chinese SIM cards can be purchased at a few phone company offices like this one. However, they usually do not offer a tourist package. Before you leave China, you will need to go back to the phone company to cancel your subscription.
N.B. The Chinese firewall applies to the mobile data using Chinese SIM cards. If a Chinese SIM is used outside China, one cannot use Google (possibly except for Google Map App)
Limited messenger apps work in China, when you need a quick chat (e.g. to open the gate).
Not many people in Nanjing speak English. However, they carry mobile phones, and may have installed translation apps.
Information in English can be found at e.g. Wikitravel, Nanjing Municipal Tourism Commission, Nanjing city
Online magazine: The Nanjinger
Small restaurants do not have toilets. There are many public toilets on the street, though likely to have no toilet papers. Buy it and bring your own.
Timetable can be found here. There are three ways to book a high-speed railway ticket.
Foreign passengers in high-speed trains are controlled by passport, so theoretically paper tickets are not needed. In order to reimburse the ticket fee, we need an invoice called 发票(fāpiào), or a paper ticket called 凭证 (píngzhèng) which can be issued at the ticket office.