Q: I remember reading somewhere that iOS 5 or iCloud now supports file attachments in the Calendar, but I can’t seem to get this working on my iPhone or iPad. Even stranger, since I setup iCloud I can’t even seem to add attachments in iCal, which I’m sure was working fine before. Am I missing a setting here or is this simply not possible?
A: Unfortunately, the handling of event attachments in the iOS 5 Calendar app can be a bit confusing. Apple actually only officially supports this feature when used with Microsoft Exchange accounts, and even in this case, there is no way to attach a file directly from the iOS device; the feature simply allows you to view attachments added from another Microsoft Exchange client and synced via Exchange ActiveSync.
Although iCal on OS X allows you to add attachments to local iCal calendars (in the “On My Mac” section), it does not provide this capability for iCloud-based calendars—the attachment option is hidden when adding or editing an event in an iCloud calendar. Further, attachments in local calendars are not transferred to your iOS device even when syncing via iTunes.
The good news however, is that it seems that iCloud actually does transfer attachments behind the scenes; it’s merely the iCal application that refuses to allow you to attach files. If you use BusyCal—a third-party calendar app that basically replaces iCal—you will be able to add attachments to an iCloud calendar from your Mac and these will sync via iCloud to your iOS device, where you will see them attached to the event and can view them from there using the built-in iOS quick viewer, in much the same manner as viewing e-mail attachments from the iOS Mail app.
Note that with iCloud, Apple places a 24MB limit on your entire Calendar and a 5MB limit on individual events, so you will want to be particularly careful about attaching large files to your calendar appointments. For large files, you’re far better off using a service such as Dropbox and simply pasting a link to the file within the notes or URL field of your event; as long as you have a data connection you can simply tap on the link to open the attachment in Safari.