I have had my Sprint Photon for about 8 months and have just now began to understand some many of the pre-loaded widgets. As for the calendar, I have discovered that if you deselect "Phone Calendar-phone storage" (on my phone this can be done in the top left corner of the widget where an upside-down triangle inside a circle can be seen) additions to the calendar on my phone were automatically added to my Google web calendar. My assumption is that someone is a business person, they may can use this function to select a specific calendar. Otherwise, any information may be added to all calendars, Google or otherwise, when someone simply enters any event on a calendar without selecting a specific account. Also, when you are about to add an event, you can select to which calendar you can add the event using the account selector at the top of the "Create Event" screen. By doing this, one should be able to manage multiple calendars (gmail, corporate, facebook, etc.), keep the info on each calendar separate, yet be able to view all info on the phone. Hope I was able to help.
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