I would suggest allowing users to supply their own wordlists, supply them with custom transliterated languages or help them create words from texts, logs, pdfs

I would suggest allowing users to supply their own wordlists, supply them with custom transliterated languages or help them create words from texts, logs, pdfs etc. Transliterating words to latin characters from a user's foreign language is a great way to add words not usually found in dictionaries. (eg If you speak Greek, French or Japanese, take a couple of books and transliterate them, remove 10% most and less common words, remove any words between 1-3 and 8+ chars and you should be gold.) You can create or find dictionaries like this for different languages and provide them for users to choose/download from. Open sourcing your app would be a great way to get help and ideas from others.