FirstLoveMovies

Young Jessie is a solitary child, and on her birthday her mum gives her a mobile phone. That afternoon the family are celebrating and her mum is electrocuted in the swimming pool. Years later Jessie finds her old mobile phone and calls her old number, and a young girl answers - her younger self. Through a series of calls the two Jessies start to change to course of their lives, both past and present.

http://www.imdb.com/title/tt1189029