This is a really valuable tool, I can vouch for it. The alternative is to make icon fonts in an app like Glyphs, which is only for the Mac. There are Linux font tools out there, but I have been disappointed by their quality. Icomoon can be a bit picky about the svgs it will accept, but with a bit of tweaking, you can get them in there. Just finished using this on a project.

I've been using this for a while, it has a pretty decent collection of icons and I love that you can import other icons to customise your font!