File upload support on mobile from: http://viljamis.com/blog/2012/file-upload-support-on-mobile/

mobile-file-upload-support

TEST RESULTS
OS   Supported?
Android 1.0—2.1	 	No
Android 2.2+	 	Yes
Blackberry 1.0—5.0	No
Blackberry 6.0+	 	Yes
BB Tablet OS 2.0+	Yes
Firefox OS 1.0	 	No
iOS 1.0—5.1.1	 	No
iOS 6.0+	 	Yes
Kindle OS 1.0—3.0	No
Maemo 5.0+	 	Yes
Meego 1.2+	 	Yes
Symbian 9.1-10.1	Yes
WebOS 1.0—3.0.5	 	No
Windows Phone 7.0—8.0	No
Windows RT	 	Yes

mobile-file-upload-support-fn

// Detect input type=file support
var isFileInputSupported = (function () {
  // Handle devices which falsely report support
  if (navigator.userAgent.match(/(Android (1.0|1.1|1.5|1.6|2.0|2.1))|(Windows Phone (OS 7|8.0))|(XBLWP)|(ZuneWP)|(w(eb)?OSBrowser)|(webOS)|(Kindle\/(1.0|2.0|2.5|3.0))/)) {
    return false;
  }
  // Create test element
  var el = document.createElement("input");
  el.type = "file";
  return !el.disabled;
})();