I enjoyed this book as I have the previous two. I have one niggle though but I stress that I liked the story. The story continues from the second book and has enough twists and turns to keep you interested. I like this series as, for me, it's a different take on a time travel story.
Too many times when reading this book, I got the feeling that the author is trying to educate me or help me win a trivia quiz. I suspect the author has spent too much time on Wikipedia to inject 'factoids' into the book. For me, it took the edge of the main character as there was no explanation (unless I missed it) for his encyclopaedic knowledge. I found this tripped up the flow of the book as these unlikely pieces of information grabbed my attention because they were unrealistic and stuck out as I read.
Examples:
Tom comments that a quote on Pinterest is from Galsworthy - Outstanding humanitarian and author who won a Nobel prize in the thirties.
Tom explains - off the cuff - that salmon and trout are from the same taxonomic family. He then explains the classification (Salmonidae) and gives examples of other fish that are part of that family.
There are many more examples and, for me, they break out of Tom's character. People don't talk like that and only experts in their field would be able to recall specific information about very specialised subjects.
Now I've got that off my chest, I reiterate, I liked the books. I have to admit that I'm slightly put off reading the fourth one though because of the Wikipedia content!