Great take on time travel. Full review to come... 
 Update 9/13/13: 
 So I just realized that I never wrote a review for this novel. I got swept up in Origin, and the review for this one just slipped my mind. Anyway...I would actually give this book 4.5 stars if I could. I was a little worried going in since this is about time travel, and time travel books can go one of two ways. It can either be really great and interesting, or just down right confusing and terrible. Usually, there's no in between. All Our Yesterdays by Cristin Terrill falls into the first category. Ms. Terrill took a very ambitious idea, and sculpted it into an amazing story that will stay with you long after you finish reading. There was the potential for this novel to be very confusing because it involves multiple timelines, dual POV's, and scientific concepts that are above most people's heads. However, Ms. Terrill handles everything expertly and the story is flawlessly written. 
 The story follows Em and Marina, who you later find out (view spoiler)[are the same person, just in different timelines (hide spoiler)]. I will say that I kind of figured this twist out pretty early on, but it was still interesting nonetheless. I loved reading each girl's perspective and respective story, and even though there is that twist, it always felt like you were reading two different people, who were just a bit similar. Each girl has their own identity, which is one of the greatest things about this novel. While this story is mainly driven by the plot, the characters don't just fade into the background. Every friendship, every romance, and every character plays a major role in future events, and is extremely believable and realistic. Nothing ever felt fake or just written as a matter of convenience. Now one of the reasons I had to give this novel 4.5 stars instead of 5 was because I couldn't stand Marina's character in the beginning. She was the typical cliche teenager that was also this "mother hen," and it just kept getting on my nerves. However, she grows significantly over the story, and everything serves a purpose in the end. 
 The world of this novel is extremely well crafted, and set up beautifully. While I would have liked a bit more background information going in, everything is revealed later on in the book. Since this is a time travel book, some liberties are to be expected. As such, you do need to go into this book with an open mind. You can't read it as this stuff is based entirely on fact. But even if you did do that, most of the ideas presented are actually quite reasonable, and I could see it making sense. Ms. Terrill does a great job at explaining all of the concepts and ideas that she has incorporated into the story so that these things aren't above the readers head. 
 However, there were 2 other reasons I couldn't give this book 5 stars. First, was that sometimes the timeline just seemed a little too unbelievable. Obviously, it's fiction and time travel, so the timeline is up to the creativity of the author, but for all of the problems to result in only 4 years, just was a bit of a stretch for me. Second, was that I still am a bit confused at the ending. I think I understand it, but I'm honestly not totally sure that what I'm thinking is correct. I saw that there is another book, so maybe it will be explained further...at least I hope. 
 Nevertheless, this was a great novel that many people will love and enjoy. It is action-packed and full of adventures. The characters and the world are unique and well-crafted. If you like the idea of time travel, you'll love this book! I highly recommend it to anyone who is looking for a new take on time travel or just looking for something different. I can already tell that Ms. Terrill is an author to watch, and I can't wait to see what she has in store for us next! Happy reading :)