A free app for Android, by MobiSystems.

French – English Dictionary is a free and convenient tool for all users who want to learn the language. It is useful for studying, for your work or for leisurely conversations with friends and family members. It is the best French – English dictionary available for Android devices. 

You can easily search for definitions, synonyms, antonyms, and verbs in the dictionary. You can also use it to search for specific words and sentences. You can choose between different language options and you can change the default language for the app. You can also add the words to your Favorites list, so you will have a quick access to the words you need.