If you download the language pack at home (go into the app and tap the download icon), you do NOT need an Internet connection. I use it all the time when I travel. The language packs are somewhat large (300MB or more), but you don't need to download more than you need. There are a few languages that are not download-able, but Chinese is a download ("Chinese" is how it is listed in the app, so I'm not sure which dialect(s) it handles, probably standard Chinese/Mandarin).