Calender application has 5 views: agenda, day, week, month and year. To quickly switch between the views of the calender application, make sure you have assigned the calender application to one of the hardware buttons*.
After you’ve assigned it to the hardware buttons, all you need to do is press the button repeatedly to cycle between the views.
* Incase you don’t know how to assign the calender application to the hardware button, go to ‘start’>’settings’>’buttons’
**tip only for windows mobile professional users only AKA Pocket PC users