I just started using CTags for php development. It allows you to move to class and function declarations. Great for large projects and unknown code.
Link to plugin: https://github.com/SublimeText/CTags
Link to plugin: https://github.com/SublimeText/CTags
CTags is absolutely fantastic though, I live and die by it in large code bases. It's backed by ctags on the system too, so it has an impressive list of supported languages.