"Tangerine" is a 2015 American comedy-drama film directed by Sean Baker. Notably, it was shot entirely on three iPhone 5s smartphones. The film follows a transgender sex worker in Hollywood on Christmas Eve as she hunts down her pimp boyfriend who cheated on her.
I think it was called Tangerine
""The speaker discusses a director he was in talks with, mentioning "Tangerine" as one of the director's notable and innovative films, highlighting its unique production method."