QuickDic

QuickDic looks up words between two languages with no internet at all. Open its dictionary manager, download the language pairs you need once, and after that every search works on a plane, on a train, or abroad with no signal.

The dictionaries are built from Wiktionary, so instead of a single translation you often get several senses of a word. Results appear as you type, and you can keep as many dictionaries on the phone as you have room for.

Because the data comes from volunteer-written Wiktionary entries, coverage is uneven: big pairs are detailed, small ones can be thin. Remember to download the dictionaries you want before you travel.