dict.cc dictionary

Dictionary for 51 language combinations, usable without an internet connection (offline dictionary). Vocabularies can be downloaded and updated within the app for free. All dictionaries are bidirectional, so German-English doubles as English-German. Just type in your keyword in either language. 

English-German dictionary: 1 million translations
The following languages are available in combination with German and English:

Albanian, Bosnian, Bulgarian, Croatian, Czech, Danish, Dutch, Esperanto, Finnish, French, Greek, Hungarian, Icelandic, Italian, Latin, Norwegian, Polish, Portuguese, Romanian, Russian, Serbian, Slovak, Spanish, Swedish, Turkish

New translations and corrections can be suggested at http://contribute.dict.cc/. Every translation gets checked by several other contributing users. The downloadable vocabularies are updated daily.

Additional features can be activated within the app.