* For iPhone, iPod Touch, and iPad
* 4.x Support for the iPad
* iOS 4 features for iPad (Multitasking, Folders, etc.)
* Updated Carrier Signal Strength Display
* Increase in the length of the smaller signal bars
* The method in which signal strength is calculated has been enhanced
* Fixes glitch that can let a user get into the phone app while the phone is locked via "Emergency Call" by dialing a random number and quickly pressing the lock button after dialing that call
* Fixes the alarm bug caused by daylight saving time changing, affected on a part of iPhone and iPod Touch owners which is located in Australia, New Zealand, and some European countries.
* iPad screen rotation lock switch is converted into a sound/silent switch in iOS 4.2 (Just like on the iPhones)
* Adds screen brightness control in the iPad multitasking tray
* Adds volume control in the iPad multitasking tray
* AirPrint Wireless Printing with Print Center
* Import .ics calendar files directly for events
* Birthdays icon has been changed in calendar
* Updated Carrier Settings (US is AT&T 9.0) (iPad 3G only)
* Text search on web pages
* 2 new fonts for Notes in Settings (Helvetica and Chalkboard)
* New icon for Voice Memos (iPhone and iPod Touch only)
* Updated applications
* AirPlay (replacement of AirTunes, AirPlay will offer stream video, music, and photos over Wi-Fi)
* More than 30 new keyboards and dictionaries, including Arabic, Greek, and Hebrew (iPad only)
* New Text Tone Alerts (New & Original tone lists) (iPhone 4 only)
* Ringer & Alerts on/off switch (Settings > Sounds) for volume buttons (iPhone only)
* Assign different text tone alerts to each contact (iPhone only)
* YouTube voting
* New Multitasking animation (iPad only)
* New Parental Controls for deleting Apps, changing mail accounts and location services
* FaceTime shortcut from Messages app (iPhone 4 only)
* New wallpapers in Settings
* New Bookmarks design (iPad only)
* Minor improvements in UI graphics
* Restores full Field Test Mode
* Added an indicator in the Appstore which shows if an App supports Game Center