支付、App、SIM 卡等实用信息。
本攻略正文目前提供英文版本，中文版正在编写中。
These are the things that catch visitors out — not the famous sights, but the small logistics that decide whether a day goes smoothly. Sorted roughly in order of how likely they are to affect you.
China runs heavily on QR payment. Set up Alipay or WeChat Pay with a foreign card before you arrive — it removes a surprising amount of daily friction. Carry some cash for small vendors, and expect international cards to work at hotels and larger shops but not everywhere.
Airport WiFi, hotel WiFi and a local eSIM or roaming plan all work. Note that many Western apps and sites are restricted — arrange a VPN before you land, because you cannot download one from inside China.
The metro is almost always the fastest option in daylight hours. Taxis are cheap by international standards; show the address in Chinese and insist on the meter. Avoid unlicensed drivers who approach you at stations and airports.
Beijing has four distinct seasons: hot summers, cold dry winters, and short, excellent springs and autumns. Air quality varies — check an AQI app if you are sensitive, and carry masks in winter.