The biggest and most obvious update is the ability for third-party applications to “multitask.” In other words, users don’t have to terminate apps in order to do something else in another app. Double tapping on the home button gives users a display of most recent apps used.
However, Apple claims that it only allows for certain functionality to preserve battery life and performance. So, it isn’t so much that apps will be multitasking, but rather, they’ll be doing a few things in the background.
For example, users can now listen to streaming music or newscasts from apps while doing other things on the iPhone. Similarly, users can now carry on Voice Over IP calls without having to quit the app to do something else.
Also, third-party apps no longer have to rely solely on push notifications to alert the user about something on the phone. An alert simply pings the user instead of having to go through a series of Internet tubes. This reduces the reliance on an Internet connection to get certain types of alerts and helps cut down on overall wireless bandwidth.
Additionally, if a user starts a task in an application, then switches to another one, it can now complete the task in the background instead of making the user wait on it.
Fast app switching allows the user to pause an app where it is, allowing them to quickly switch away from it and then switch back, picking up where the user left off.
Another update is folders, which allows users to simply drag and drop icons on top of each other to create a custom folder of apps. Tapping on the folder brings up a display of all the enclosed icons.
The new operating system also promises better mail, allowing the user to see all the messages together in a unified inbox, organize messages by threads and more.
When it comes to iOS4’s multimedia features, the iPod, music and video apps are refined rather than greatly changed.
Meanwhile, AT&T has announced that it will not be offering walk-in sales of iPhone 4 in its retail stores until June 29 as the company seeks to meet pre-order demands.