Here is the iOS 4.2 features changelog:

Multitasking


iOS 4.2 includes the multitasking feature for the iPad, which will finally allow users to run some third party iPhone apps to run in the background. iPad users will be able to access seven apps in the task switcher in landscape mode and six apps in portrait mode.

Read on for the full changelog.


Folder Management 


iOS 4.2 brings Folder Management feature to iPad users. Users can add up to 20 apps to a folder. You can currently add only 12 apps in case of the iPhone and iPod Touch but a cydia hack- infini folders bypasses this restriction.

Threaded Mail App


The mail app on the new iOS 4.2 comes with a universal inbox that aggregates messages from multiple email accounts.

Mute Switch

The screen orientation lock switch on the iPad has now been repurposed to serve as the mute switch. With this, users may now access the screen orientation lock from within the multitasking tray.

Game Center


Apple's social gaming network will make its debut on the iPad with iOS 4.2. The Game Center application makes use of the larger screen of the iPad to display a double-column view instead of the standard single column view of the iPhone. The left column contains the lists while the detailed view of stats shall appear on the right column.

New Fonts


With, iOS 4.2 you can change fonts in the Notes app. 

New Settings Options




The iOS 4.2 Settings offers a number of new options and preferences. The Spotlight Search Preference pane lets users include search results based on a number of categories like Contacts, Applications, Music, Podcasts, Videos, Audiobooks, Notes, Mail and Events.

New Lockscreen Keyboard 


If you have disabled the simple passcode feature in Settings and instead opted for an alphanumeric passcode, you will notice a different black-colored keyboard on the lockscreen.

"Find" feature in Safari



New find feature has been added to Safari.

New Alerts


Alerts now have silvery shadow effect.

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