Internet, phone and plugs

The simplest solution if your phone supports it: buy it online before leaving, activate it on landing, and keep your usual number for your bank's text messages. Data only. Allow roughly ₩15,000 to ₩40,000 for one to two weeks depending on volume.

Sold at the operators' counters in the airport arrivals hall on presentation of your passport. Its advantage: some plans include a Korean number, useful for a few apps and bookings.

A small box rented at the airport that shares its connection between several devices. Worthwhile for families or groups; charge it every night and return it before you leave.

Korea falls outside the zones included in most European and North American plans. Check your operator's rates before leaving, and switch off data roaming if you take an eSIM.

Naver Map, Kakao Map, Papago, KakaoTalk (sign-up with a foreign number), k.ride, Uber, the English-language train and bus booking sites.

Food-delivery apps, virtual queues at some restaurants, Korean ticketing sites and some online shopping require identity verification tied to a Korean number. Ask at your hotel reception: many will gladly help.

The messaging app the whole country uses. Install it: this is how guesthouses, agencies and the Koreans you meet will reply to you.

Install and test everything before leaving, while you can still receive confirmation texts at home.

220 volts, 60 hertz, round two-pin plugs of types C and F: the same as in most of continental Europe. No adapter is needed for a French, German or Spanish appliance.

Travellers from the UK, Ireland, North America, Australia, Switzerland or China: bring an adapter, and check that your devices accept 220 volts.

Sockets and USB ports on high-speed trains, premium buses, in cafés. Power banks can be rented at convenience stores.

Korean airlines apply strict rules: power banks in the cabin only, kept on your person and not in the overhead lockers, and in limited numbers. Check your airline's instructions.