This is one of those rare instances in which I wish there were 1/2 star gradations and I had a hard time deciding between 3 or 4 stars. I enjoyed this audiobook but for much of the first half I felt disconnected from the book - admiring the craft without being drawn in to the story. I would rate the first half of the book a 3 star read and the second half a 4 star. The narrator was excellent, one of few I have found who consistently came across as being the character they are conveying rather than just reading the character's lines. 
 The story of Sam (Samantha) reliving the same day over and over (yes, I've seen Groundhog Day and this book deserves far better than that comparison) as she learns how her actions influence those around her has the potential to be a repetitive and tiring storyline but it wasn't at all. The changes Sam makes with each restarted day and her changing perspective on her life keeps each redo fresh and interesting. Sam and her friends are not black-and-white character studies even at the start and the insight we get as the story progresses makes that more true. The story craft employed was excellent and makes the character arc/growth utterly believable; a very compressed analogy to the way life's events mature us from narcissistic children to outward looking adults. 
 I found little to connect with personally in the first half of the book but by the second half, despite still not finding much to self-identify with, I was completely invested in Sam and her journey and anxious to find out what the resolution would be. It was a difficult ending to read but the right choice for the story. Overall a recommended read.