and if you actually looked at all of those calendar applications, you'd see that none of them are actually new calendar systems. they're all widgets and things

and if you actually looked at all of those calendar applications, you'd see that none of them are actually new calendar systems. they're all widgets and things that just display the data in the calendars already on the phone. even if they created a new system calendar, it still has to sync to an account, which i already stated is limited to a google or exchange account. otherwise, it would be creating a calendar that only that application can manipulate, which would not work with all of those other widgets and things that tie into the phone's data.