In reply to TheDrunkenBakers:
You can control which calendars are actually displayed in your Google Calendar app and turn them on or off whenever you fancy, or stop it from syncing to your phone at all.
If you still want the work calendar on your phone but want it in a completely separate app, you could install the Exchange app or one of the many alternatives that will display an Exchange calendar.
Or you could keep your work calendar displaying in the Google Calendar app, not display your personal calendar and install another app that plays nice with Google Calendar to display your personal one.
Myriad options. Personally, I find it useful to have everything in one place on one app. When I only want to see one particular calendar, I can just hide the others.