While I didn't end up changing wheel color, I found a way to change the label some time ago, and wanted to share for anyone that may want to do something similar. When instantiating mobiscroll, I use the following code:
$(".datePicker").mobiscroll().date({
theme: 'jqm',
display: 'bottom',
onChange: function(valueText, inst) {
var selectedDate = new Date(valueText);
$('.dwv.ui-header').html(valueText + " - " + getShift(selectedDate) + " shift");
},
onShow: function (html, valueText, inst) {
var selectedDate = new Date(valueText);
$('.dwv.ui-header').html(valueText + " - " + getShift(selectedDate) + " shift");
}
});
That gives me a label for the date/datetime picker that looks like "04/09/2014 - B shift", that updates as the selected date changes.