Our friends over at Gizmodo has just reported that Apple has sent out invitations to an iPhone OS 4.0 preview event this coming Thursday 8th April at 10am pacific time, to take place at their Cupertino California Campus.
Rumours around the iPhone OS 4.0 has been going around since the start of the year, but recently they have increased, including news that it is likely to bring multitasking through Expose like interface, something that iPhone users have been asking for since the dawn of time (or at least since the launch of the iPhone).
Other features of the iPhone OS 4.0 that are doing the rounds in the rumor mill are unified inbox for multiple email accounts, and new multi-touch gesture support.
At the moment it is believed that the new iPhone OS 4.0 firmware will be released around the same time as the new 4th generation iPhone, which is rumoured to be out in June/July time this year.

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