Apple's yearly developer conference should see iOS 8, OS X 10.10, and likely some hardware.
Apple to Hold Early April Media Event for iOS 5 and MobileMe Revamp?
Attendees waiting outside Apple's iOS 4 event on April 8th, 2010
German site Macerkopf.de claims [Google translation] to have received word from a source that Apple is planning an early April media event to introduce iOS 5 and revamped MobileMe services. The report seems to indicate that the event would take place on Apple's campus in the 14th or 15th week of the year, which would be the first or second full week in April.
An early-to-mid April developer event to show off the next-generation iOS version would be in line with Apple's pattern in recent years as it seeks to get third-party developers on board ahead of a public release in June or July alongside new iPhone hardware. For example, last year's iOS 4 event took place on April 8th at the company's headquarters in Cupertino. We do not, however, have much of a track record for Macerkopf.de when it comes to rumors, so it is difficult to assess a level of confidence in the claims.
Previous claims had "almost guaranteed" that last week's media event would see a preview of iOS 5 and cloud-based services, but those topics were not included with the iPad 2 unveiling.