The latest smartphone platform from Apple, the iOS 4, brings in many new and highly desirable features to the Apple handhelds - both iPhones and iPods. This new OS is compatible with iPhone 3G, iPhone 3GS, iPod Touch (2^nd Generation) and iPod Touch (3^rd Generation), apart from iPhone 4. The new features of this OS have been listed below:-

Multi-tasking

This is the most note-worthy inclusion of the iOS4. However, multi-tasking is limited to only certain tasks. They are:-

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  Streaming music - You can listen to music from apps like Pandora, while checking your mail or SMSing or viewing your photographs and more. In the previous iPhone OS, you had to stop the music app first, if you wanted to do anything else.

  
  


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  Location based activities (GPS) - The GPS can work in the background to find out your geographical location, when you're doing something else - say mailing or playing games. This was not possible in previous operating systems.

  
  

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  Downloading - Here again when you're downloading a file on the iPhone, you need not sit tapping your fingers on the table. You might as well do other productive things like watch videos, take pics, email or so.

  
  

Other tasks will not run in the background when you're doing stuff in the foreground. They will merely be paused when you switch to another application. When you switch back, they will resume from where you left them. This has been so designed to conserve the energy of the device. Otherwise, all tasks running together can drain out the battery faster.

Double tap the home button and you will see a bar which displays all active apps. You can touch the app you want to switch to.

Note:- Earlier, double tapping the home button popped up the iPod controls. Now, in-order to see iPod controls, you need to first double tap home button and then swipe right once.

	iPhone 3G	iPhone 4, iPhone 3GS
Multi-tasking	No	Yes

Email Enhancements

The business-men and professionals will definitely appreciate this feature.

• Single View, Multiple Accounts - If you have multiple email accounts, you can view mails from all together. So you don't have to switch from account to account, to check your mails.

• Threaded Emails - Threaded emails are also supported. You can thus see all mails from a particular contact without having to search for each of them.

Note:- However, sent items will not be included in the threads. You'll have to go to the "Sent Items" folder to see them.

.	iPhone 3G	iPhone 4, iPhone 3GS
Email Enhancements	Yes	Yes

Folders

Apps can be arranged into folders for easy management. Hold your finger on an icon. The icons will then go shaky. You can now drag and drop one icon on another. This will create a folder with the 2 apps inside it. You can similarly drag and drop more icons into the folder. A folder can have a maximum of 12 apps. There is however, no direct way of creating a folder, like you would on a laptop or PC.

.	iPhone 3G	iPhone 4, iPhone 3GS
Folders	Yes	Yes

Creating Playlists

Playlists can now be directly on the phone, without having to hook it to a computer and doing so using iTunes.

.	iPhone 3G	iPhone 4, iPhone 3GS
Creating Playlists	Yes	Yes

iBooks

The iBook store which gobbled quite a big chunk of the spotlight when the iPad was announced, is now making its way into the iPhones, thanks to iOS4. You can thus read books whenever you want and carry them with you for no extra weight.

.	iPhone 3G	iPhone 4, iPhone 3GS
iBooks	Yes	Yes

Background wallpaper

Instead of having the boring black background when navigating through apps, you can now set an image as a background wallpaper.

.	iPhone 3G	iPhone 4, iPhone 3GS
Background Wallpaper	No	Yes

Spell Check

As and when you're typing, you will get a red line under words that have been misspelt. By touching the word, you will get the correct word option. Touch on this word option to replace the misspelt word.

.	iPhone 3G	iPhone 4, iPhone 3GS
Spell Check	Yes	Yes

Faces and Places Options with photographs taken

The iOS4 brings 3 new things in the photography realm:-

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  Digital Zooming - 5x zooming when taking photos or videos. However, this zooming is only limited to digital zooming or enlarging the object without actual optical zoom. Hence the clarity will be lost as you zoom in more.

  
  


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  Geo-tagging - Photographs can be viewed on a map, i.e. The map will show which locations what photographs have been shot.

  
  

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  Face-tagging - Photographs can as well be face tagged according to your contacts or friends. Thus you can view photos, contact-wise.

  
  

.	iPhone 3G	iPhone 4, iPhone 3GS
Faces and Places Options	Yes	Yes

Using a Bluetooth Keyboard

You can use a wireless Bluetooth Keyboard to enter content into your iPhones.

.	iPhone 3G	iPhone 4, iPhone 3GS
Using a Bluetooth Keyboard	No	Yes

Bing

Bing has been added to the search engine list now.

.	iPhone 3G	iPhone 4, iPhone 3GS
Bing	Yes	Yes

Locking orientation

You can now lock the landscape or portrait orientation if you do not want it to change when you're turning the phone. To activate this, double tap on the home button. Swipe right to get the iPod controls. There you should find the orientation lock button. Tap on it. Once orientation lock is activated, you should see a tiny icon on the top right corner of the screen near the battery indicator on the phone.

.	iPhone 3G	iPhone 4, iPhone 3GS
Locking Orientation	Yes	Yes

Searching through Text Messages

The iOS4 gives you the ability to search your text messages (SMS) apart from the Inbox.

.	iPhone 3G	iPhone 4, iPhone 3GS
Searching through text messages	Yes	Yes