Futuristic movie with a totalitarian government consisting of seniors, where the protagonist learns of colors from an apple

Is it possible that you're thinking of the 2014 adaptation of The Giver?

Following a calamity referred to as The Ruin, society is reorganized into a series of communities, and all memories of the past are held by one person, the Receiver of Memory. Since the Receiver of Memory is the only individual in the community who has the memories from before, he must advise the Chief Elder, and the other Elders, on the decisions for the community.

Jonas (Brenton Thwaites) is a 16-year-old boy who is anxious about the career he will be assigned (along with everyone else). His two best friends are Asher (Cameron Monaghan) and Fiona (Odeya Rush).

On the day of graduation, everyone is assigned a career. Jonas is briefly skipped, as he has not been assigned a career. Instead, Jonas is to become the next Receiver of Memory, and progressively receive memories from the past receiver, The Giver (Jeff Bridges). Upon assuming his role as The Receiver, Jonas learns of the Giver's past and of his child, Rosemary (Taylor Swift), who preceded Jonas as Receiver of Memory. She was so distraught from the memories that she committed suicide, by what the Community calls "releasing". They regard its nature as mysterious; the audience learns that it is death by lethal injection. Jonas begins to teach his findings to his friend Fiona, with whom he decides to share the idea of emotions. Fiona, who is unable to fully comprehend the idea of emotion, is unsure how she feels. Jonas then kisses Fiona, an action which is antiquated and unknown to the community, which Jonas gained through memory....

As you can see, the film does transition from black-and-white to color (54 seconds in):

In Chapter 3 of the book, it's revealed in a flashback that the first hint that Jonas can potentially see color involves an apple which briefly changes before shifting back to seeming normal. I'm not certain if the same scene shows up in the film, but the second official trailer does show him realizing colors from an apple.