In the discussion you disclose various formats for web icons needed for various things.
If users want an APP for that, @Doobox makes a nice App that will take an image, make a PNG and ICO file for your website out of it. The ICO file contains the 3 sizes required. Does nothing for SVG format though.
It’s useful, inexpensive and saves a whack of time…
I haven’t used the app from @Doobox yet but I’ll play around with it and all the other stuff from them. @Doobox had a great mega bundle deal and I got the whole lot – including the kitchen sink.
Anyway, if you want to convert SVG into icons, you might want to try Iconverticons.
One thing to check with ico and web images created by online and App generators, is the size of the files they generate. Some are absolutely huge!
I generated a very simple ico file with an App and it created a 75K ico, yet the same original optimised png was 0.5k. Even the web images are a few Kb but at least you can optimise the pngs.