audio descriptions?

Hello guys!
Are audio descriptions only available on movies bought on iTunes or on trailers as well?
I live in Brazil, and some movies are with the information to have audio description but when I went to watch the trailer, nothing happens. I have the option enabled on my iPhone

Forum: 

#1 re:audio discription

Hello! in the movie page, cross between the headings and looking for accessibility, orthe words "audio discription" or the letters "AD" that's means for audio discription. if it turned on on your device it should work. in Israel was time that i can't find moovies with audio discription, but now it does work fine and it's very fun to watch this.

#2 Trailer?

Hello! Does it also work in the trailer?

#3 Some Do, Some Don't

Hi Diego. I don't yet have an iPhone but think I can answer your question. Some movie trailers do contain AD, but it seems most still do not. I think it depends primarily on the producer. I don't know if you've heard about the Audio Description Project or read about it, but they're frequently updating their website with new information. Check them out at http://www.acb.org/adp . It seems to be mostly US-based but other countries are also represented. Hth and take care.

#4 no

Hi, no it doesn't work in the traler only the moovie self it was usefull if it does work with this.