I don't usually gravitate towards thriller / mystery books, but this one really caught my interest due to the inclusion of social media which I thought would be intriguing. I was completely correct with this, I loved the online aspects and it added so much suspense to this book and felt very 21st century. I really enjoyed the reading experience and found it so hard to put down this book, but I found myself feeling so incredibly let down and disappointed by the big reveal in the book, who the killer was. It was so blaringly obvious, I really thought it was too obvious to be the character in question so tried to speculate otherwise, but it was just too obvious it literally could not have been anyone else, the author very much spoon fed 'whodunnit' to us from the very beginning and this was such a let down. This book had 5 star potential was it not for this ending.