@Font-face not working on mobile

You need to add all src needed to @font-face like this example:

@font-face {
  font-family: 'MyWebFont';
  src: url('webfont.eot'); /* IE9 Compat Modes */
  src: url('webfont.eot?#iefix') format('embedded-opentype'), /* IE6-IE8 */
       url('webfont.woff2') format('woff2'), /* Super Modern Browsers */
       url('webfont.woff') format('woff'), /* Pretty Modern Browsers */
       url('webfont.ttf')  format('truetype'), /* Safari, Android, iOS */
       url('webfont.svg#svgFontName') format('svg'); /* Legacy iOS */
}

Source: https://css-tricks.com/snippets/css/using-font-face/
Hope it helps, cheers.

(If you need to convert the font you gonna need this font-generator )

You haven't included (assuming you have them) all the necessary font files:

@font-face {
  font-family: 'Out';
  src: url('out.eot'); /* IE9 Compat Modes */
  src: url('out.eot?#iefix') format('embedded-opentype'), /* IE6-IE8 */
       url('out.woff2') format('woff2'), /* Super Modern Browsers */
       url('out.woff') format('woff'), /* Pretty Modern Browsers */
       url('out.ttf')  format('truetype'), /* Safari, Android, iOS */
       url('out.svg#svgFontName') format('svg'); /* Legacy iOS */
}

So *.ttf is missing for Safari/IOS etc.