I am using bootstrap datepicker and my code is like following, Demo of the code on jsfiddle
For the latest bootstrap-datepicker (1.4.0 at the time of writing), you need to use this:
bootstrap-datepicker
$('#myDatepicker').datepicker({ format: "mm/yyyy", startView: "year", minViewMode: "months" })
Source: Bootstrap Datepicker Options