Possible problems are the default index.css in cordova. Check if the body element has the style defined for " text-transform: uppercase ".
At least this was a problem for me, after removing this default body element index.css, if you use it in your application, can also help you.
For me, I used the gurmukhi / punjabi fonts, and after removing the line from index.css it just worked like a charm with below css definitions
Example:
.demo { font-family: anmol } @font-face { font-family: anmol; src: url(../fonts/anmol.ttf); }
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