Turtles All the Way Down by John Green is a 2017 YA fiction that many enjoy. It focuses on Aza, a young girl with anxiety and OCD. She gets involved in a mystery involving a fugitive billionaire. Along the way, she has to deal with her mental health issues, her relationships with her friends and family, and the mystery itself. It's a poignant look at living with mental illness while also being a bit of a mystery story.
The Hate U Give by Angie Thomas is an excellent 2017 fiction for young adults. It deals with the important topic of police brutality and racial inequality through the eyes of a young girl, Starr. Starr witnesses the shooting of her unarmed friend by a police officer and has to find her voice to speak out about it, all while dealing with the normal pressures of being a teenager.
Simon vs. the Homo Sapiens Agenda by Becky Albertalli is also a great 2017 YA fiction. It's a heartwarming and funny story about Simon, a closeted gay teen who is blackmailed by a classmate. As he tries to figure out who is blackmailing him, he also navigates his feelings for another boy, Bram. It's a story about self - discovery, friendship, and first love.