Applications keep rolling in for the iOS 4 and there is no stopping them. Today’s popular app is a popular one that many have probably heard of before: Skype. One of the largest VoIP providers out there just released a brand new version for Apple’s new mobile Operating System and it comes with a plethora of changes and features.

The update brings forth version number 2.1 and it looks like the Skype developers have been listening to users about what they want. One of the biggest features is that you can run the software in the background, no matter what else you find yourself doing. This means that you can still get those instant messages, as well as receive calls even if you aren’t running the app, or find yourself playing some games. Skype will even work when the phone is locked. A big improvement over previous iterations. A word of caution though, multitasking is only available on the iPhone 4 and iPhone 3GS, so for you iPhone 3G owners out there, no official Skype multitasking for you. We’re still hoping that video chat makes an appearance at some point but we won’t be holding ou for it. Calls are still free too by the way and so is the app itself. If you decide to check it out, you can download it from iTunes here. Let us know what you think of the changes in the comments below!