For example in app.html.eex template both the following lines work…
<link rel="stylesheet" href="/css/app.css">
<link rel="stylesheet" href="<%= static_path(@conn, "/css/app.css") %>">
Or in another template:
<img src="/images/none/80x80.png" alt="photo">
<img src="<%= static_path(@conn, "/images/none/80x80.png") %>" alt="photo">
I would like to know If there is no problem not using it… Maybe that just works because I am in dev environment ?