Help!

Since I started reading a lot again I've been cranking through books.  And spending a lot through the Kindle store.  I'm looking for recommendations for either free reading apps or free books you've read through the kindle store that were good.

A Simple Favor by Darcey Bell

Stephanie was overjoyed to have finally found a friend after her husband's death.  Emily is the mom of a boy Stephanie's son is friends with.  And she gets it.  She's understands the struggle of being a mother and she is also a working mom to boot.  Stephanie doesn't work so she often helps get the boys after school and watches them until Stephanie can pick her son up.  But one evening she doesn't come.  Stephanie thinks she must have misunderstood and keeps Nicky another day, but Stephanie doesn't pick him up the next day either.  Stephanie realizes her friend is missing and must uncover what happened to her, for Emily's family and for herself.

This ended up on my reading list after I saw the commercial for the movie.  I like to read the book first.  But the trailer looked suspenseful, which I liked.  It was a very interesting story and I honestly couldn't have predicted much of it at all.  Anyone see the movie?  Was it worth seeing?