This app was mentioned in 5 comments, with an average of 3.00 upvotes
Alemão-Inglês (e vice versa) uso este no Android: https://play.google.com/store/apps/details?id=de.reimardoeffinger.quickdic
Na web tens este: http://dict.tu-chemnitz.de
Se calhar não é bem o que queres, mas para coisas gratuitas (e offline no caso da app) gostei bastante.
Check out QuickDic, it uses Wiktionary data and can display the Wiktionary website for conjugations. It's not design solely around Finnish and its conjugations, but it often suffice.
I use QuickDict, baset on Wiktionary. Very simple, works well