There is no easy way to achieve that. What you need to do there is to build a native plugin that will open a custom dialog when you click on a <select>.
That dropdown you want to get rid of is the default view for selects on webviews, opposed to the second one that was built in chrome. To help getting you started:
//get all the options and store in an array
var values = $.map($('#group_select option'), function(e) { return e.value; });
//Native function that gets the options and display a dialog
function void showDialog(String[] values){
AlertDialog.Builder b = new Builder(this);
b.setTitle("Example");
b.setItems(values, new OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
switch(which){
case 0:
//call some javascript method to use this value here
break;
case 1:
//call some javascript method to use this value here
break;
}
}
});
b.show();
}
Make sure to set your theme to Holo or Holo.Light as you prefer, and do your preferred bit to call a native code from the javascript layer whenever there is a click on a select element.