The right answer is a pair of apps with different jobs, plus one piece of preparation that matters more than the choice between them.
Pleco, for characters#
Pleco is the dictionary. It looks up characters by handwriting, by pinyin, or by camera, and its OCR reads a menu or a sign and tells you what each character means rather than producing a guess at the whole phrase.
The decisive feature is that it works entirely offline. No signal, no VPN, no data plan — which matters on a train through Gansu or in a restaurant with concrete walls.
Google Translate, for sentences#
Google Translate handles conversation, whole sentences and the "show this to the driver" case that a dictionary cannot.
The catch is that Google is blocked in mainland China, so the app only works if you downloaded the offline Chinese language pack before you arrived. Do that at home, alongside your offline maps. With the pack installed, camera and text translation both work without a connection; without it, the app is a blank screen on the day you need it.
Baidu Translate or Youdao, behind the firewall#
If you are on a Chinese SIM without a VPN, Google will not reach the internet at all. Baidu Translate and Youdao are the domestic equivalents, both good, both with camera translation, and both entirely unaffected by the filter.
This is worth installing even if you plan to roam on a foreign SIM, because it costs nothing and covers the case where your data arrangement fails.
The preparation that beats all three#
Screenshot your hotel name and address in Chinese characters. An image works with a dead signal, a dying battery and a driver who does not read Latin script. It turns the hardest daily problem — getting home — into a two-second exchange.
Do the same for anywhere you must reach at a fixed time: a station, a clinic, a tour meeting point. This single habit removes more friction than any app.
What the apps are bad at#
Menu translation produces nonsense. Chinese dish names are frequently poetic or historical, so an app will hand you "Ants Climbing a Tree" (minced pork with glass noodles), "Lion's Head" (a pork meatball) or "Husband and Wife Lung Slices" (which contains no lung). The translation is literal and correct; the dish is not what it sounds like.
Spoken translation struggles in noise, which is most restaurants. Typing is more reliable than speaking.
Medical and administrative situations need precision an app cannot guarantee. That is an argument for an insurance assistance line rather than a better app.
For the phrases worth learning anyway and how tones work, see Mandarin phrases for travellers; for what else to install before you fly, the internet, VPN and apps guide.