The latest version of the iPhone operating system, now known as iOS 4, is finally available for public download.
As with the earlier versions of iOS, the latest version too has incorporated some major new features like multitasking, folders and a lot of subtle changes that may not be apparent immediately.
Here is a list changes that have been noticed in iOS 4 so far.
1. On-Call Screen
The "End Call" button on the iPhone's call screen has now been replaced with a text that reads "End". The End button is now in a sober shade of red. You may also notice that the contact's photo now extends till the bottom of the screen and is visible beneath the End button.

2. Mail Draft
In earlier versions of iOS, if you tapped on the cancel button while composing an email, you got three options that read "Save", "Don't Save" and "Cancel". These options have been replaced with "Delete Draft", "Save Draft" and "Cancel" in iOS 4, which seems more appropriate.

3. Shorter Address Bar on Safari
The address bar and search field on the Safari app are now shorter. That means it takes up less screen space as you can see from the image below.

4. iPod Album Listing
Browsing albums have traditionally displayed the tracks and the shuffle option. In iOS 4, the iPod app now provides more details of the album such as the album thumbnail, track count, length of tracks and album release date.

5. Alerts and Notifications
There are a lot of minor tweaks in the error messages and other system notifications. For instance, notifications regarding an app's age rating now explicitly mentions the iPhone application name in the warning dialog though 'Tap' rather than 'Click' would have been even more accurate.

The error messages are slightly more informative in iOS 4. For example: the "no Internet connection" notification in iOS3 has now been replaced with a message that reads “The Internet connection appears to be offline”
6. Maps app
iOS 4 introduces minor changes to the iPhone maps application. iPad users may have already noticed several of these changes with iOS 3.2. Firstly, changing map tiles on iOS 4 displays the familiar iPad 'fade-in'. The GPS icon has now been changed to an arrow and is displayed on the status bar. Also, users may now hold their finger on a location to place a new pin. Additionally, 'Dropped Pins' may now be accessed from the Bookmarks.
7. Homescreen Changes
The homescreen animations are similar to what users may have observed on the iPad. The application dock slides down when an app is launched and slides up when the user closes the app and returns to the homescreen. Also, when you delete an app, the (X) button against the particular wiggling app icon is displayed in a pressed state - as you can see for the Twitter icon in the image below.

8. Birthday Calendar
The Calendar app gets a Birthday calendar in iOS 4 that consolidates the birthdays of all contacts from the address book.
9. Photo app
Though you could see photos in landscape and portrait mode in iPhone's Photo app, you could check the photo album listing and thumbnails only in portrait mode. The Photo application in iOS 4 now completely works in landscape mode. iOS 4 also uses a new auto-sizing feature that will fit the photo to the screen by default.
Kudos to Nik Fletcher and Ryan Poole for identifying these subtle changes in iOS 4. It's one of those things we really look forward to, after a major iPhone software update.
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At least one person has received their iPhone 4 early, but San Diego-based lawyer Gil Cabrera says he can’t activate his new phone yet.
“Xmas has come early because my #iPhone4 just arrived,” Cabrera tweeted earlier. But he later said, “Oh cruelty! Apparently, the #iphone4 arrived in error early and I cannot activate it until tomorrow! That’s just wrong!”
Here’s a few pictures of the phone that Cabrera uploaded to TwitPic.


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You might as well throw your sleeping bag and Coleman stove back into the attic, as AT&T as just announced that due to incredibly strong demand, it will not have any iPhone 4 units for sale in stores until June 29th. Anyone who pre-ordered for in-store pick up or home delivery will get their device on launch date provided they ordered before that infamous cut-off.
Here’s AT&T’s statement:
Preordered for home or business delivery: iPhone 4 will begin arriving this week for customers who preordered. We’ll send an email when each order has shipped.
Preordered for store delivery: AT&T retail representatives will begin calling customers this week to let them know their iPhone 4 is available for pick up in store.
Retail purchase (no preorder): AT&T plans to have iPhone 4 inventory – available on a first-come, first-served basis while supplies last – on June 29 in its retail locations, at
www.att.com and in business sales channels. As inventory sells out, AT&T will offer the convenient option of purchasing iPhone 4 and having it delivered to a home or business or an AT&T store. As always, customers will receive an email once their order is placed, and again when it ships.
Anyone sharpening their pitchforks?