I have seen various discussions on Words with Friends discussion boards concerning the use of Word finders. Remember that the Words with Friends application already has a word checker. You simply cannot place an illegal word.
I have three views on using Word finders
1. Be Open: There should be an agreement between the players whether to allow their use or not. As I said above, I play Scrabble in French and I use, with my friend’s permission, a dictionary. As I have improved it is used now mostly for checking spelling or for checking French verb conjugation which is 50 times more complicated than my beloved English.
2. It can teach: I would encourage novice players to ask if they could use one, when playing a better player. As I have proved to myself, a novice player will benefit from their use because the word finder will suggest words that they had not though about and the novice will begin to understand the versatility of the game and their vocabulary will improve.
3. Otherwise: If there is no agreed use or no discussion about their use it is simply cheating.