Add AM/PM to datepicker?

This will depend on the settings of the user. If you go to Settings -> General -> Date & Time. there is a "24-Hour" time switch, and based on that users will have the AM/PM indicator on your picker.

Unfortunately UIDatePicker doesn't have an option for that; it always respects the device option of 12-hour or 24-hour time.

If you must have an AM/PM component you may have to go with a custom UIPickerView instead, and build an NSDate out of its components manually.