If you are searching for a flat icon free commercial use, then [FREEBIE] Flat Icons (.psd/.sketch) is the choice for your blog. Here we have for you a set of Free [FREEBIE] Flat Icons (.psd/.sketch) which you can add freely to your library.
Download modern UI style icon file and use it as you wish to use it. Many thanks to Dribbble.com.
If you want more icon, you can check the Free Icons.