I did not like how it changed everything- left out my favourite bits, relationships, characters, and instead added scenes that were somewhat stupid.
Here is a list of things I hated: The lack of Christina+Will relationship, the lack of Al being important, The lack of Uriah and Marlene, They changed the order of everything (tris is supposed to go to Erudite after she kisses Four, and then gets in trouble when she comes back, but that never happened), How horrible the family visiting day scene was (I still don't understand why her mother wasn't allowed there), No Edward getting stabbed, Four's fear landscape was handled diffrently and they cut my favourite part, Tris's fear landscape only had 4 obsticals instead of 7, The part where Tobias is running the computers, they are supposed to be alone!!! Jeanine isn't supposed to be in that scene! In the book, Jeanine never gets stabbed by Tris, and never gets put under the Serum (SHE IS SUPPOSED TO BE DIVERGENT), Tobias is supposed to shut down the simulation, not Jeanine!
List of things I liked a lot: AWESOME visuals, The scenes that were done right were awesome, I loved the crow simulation, good acting
If you haven't read the book, You would probably really enjoy this (most of my friends did), but if you are the kind of person who will say "That didn't happen in the book!" Then this may not be for you. I give it 7/10 in total.