This app should be multilanguage (translated to most languages).
My next suggestion is to add possibility to upload/download specified specified language file.
There should be a list of languages and a list of language files, option to rate, comment etc. present databases.
There should be one main public database under watch of the moderator.
Dictionaries may be edited and developed by communities in order to make using of the Nokia Device better :)
When we upload our own database, there should be possibility to compare words with the mentioned "main" database and if there will be new interesting words than moderator may add/accept new words to the database. :)