For those on MacOS, I suggest this port of emacs : https://bitbucket.org/mituharu/emacs-mac/
It's basically the same as the distribution from http://emacsformacosx.com, but it supports various enhancements made for mac, eg. resize text size with trackpad, smooth buffer scrolling and SVG support, which is quite convenient when used with the jupyter notebook interface and producing plots. See for instance : http://imgur.com/gallery/vEI2z.
As an aside, I'm looking forward to better support for text scaling in future [2,3] as it's a feature that (if it was compatible with autocomplete and company-mode) fits my workflow better than zoom-frm.
[1]: https://github.com/railwaycat/homebrew-emacsmacport
[2]: https://github.com/company-mode/company-mode/issues/299