Here’s my current recommendation based on what I have read myself so far…
- Programming Elixir (Pragprog) the first 50%
- Elixir In Action (Manning) in full
Programming Elixir - the remainder - Learn Functional Programming with Elixir (Pragprog)
- Programming Phoenix (Pragprog) up to just before you start the main project
- Programming Ecto (Pragprog) in full
- Programming Phoenix - the remainder
Why?
Programming Elixir and Elixir In Action are a fantastic combo because they cover much of the same ground, so reading them like this means you don’t really have to make notes as you’ll be repeating what you’ve learnt (which reinforces what you’ve learnt). You could probably just read Programming Elixir first then Elixir In Action mind (or the other way round if you wanted to). They are both must-reads as you get to learn about Elixir via two different (and very well respected) authors who have two different styles and approaches to the subject.
At first I thought Learn Functional Programming with Elixir would have been a great ‘first’ book when coming to Elixir, but after reading it I was glad I read it after Programming Elixir and Elixir In Action because it doesn’t really teach you the fundamentals of the language like those two do; it is more focused on functional programming (and that is very handy, particularly when you start to look at things like Phoenix and Ecto and are gearing up towards writing your first project).
The reason why I feel reading the first couple of chapters of Programming Phoenix before reading Programming Ecto is because by the time you finish Learn Functional Programming with Elixir you will be itching to get into Phoenix (as it may feel like you have waited long enough! 
) plus I really loved the first couple of chapters of Programming Phoenix and by the end of them, you will be the most excited and motivated you have been to date 
I have written reviews of all of the books I have finished and they go into a bit more detail if you fancy taking a look:
Not a review but my thoughts on the initial chapters of Programming Phoenix → Programming Phoenix (Pragprog) - #18 by AstonJ 
One thing is for sure, we are very lucky to have so many Elixir books and I can’t wait to read the rest of them
