php-hover-documentation
A simple Atom package that displays the definition and description of PHP functions when you hover their names.
PHP Hover Documentation
PHP is nice, but it lacks a bit of standardization, which can make its built-in functions hard to use.
This simple package adds a tooltip with the definition and description of PHP's built-in methods when you hover them. It's nothing fancy, but it saved me a lot of time, and I bet it'll do the same for you!