My first language is English, my second language is French. My iPhone interface/input language is French but I use a lot of apps in English. I wish the individual apps would allow me to pick and choose which language I prefer to use, regardless of the cell phone’s input language. Some apps automatically default to the language chosen based on the cellphone’s input language, but perhaps some people may not want that. I think that restricts the user from using the app based on their personal language needs. This becomes more evident, especially if a person speaks, works, and interacts in more than one language.