Jailbreakers Discover Issues with Skype Multitasking
Posted 07/22/2010 at 5:50am
| by J.R. Bookwalter

There was a collective sigh of relief when a new version of Skype showed up in the App Store on Wednesday, adding iOS 4 multitasking and the ability to run the app in the background, allowing you to receive calls or chats anytime. There’s just one problem: It doesn’t work if your device is jailbroken.
Skype updated their iPhone app to version 2.0.1 on Wednesday (despite the app itself claiming the version number is 2.1), adding the long-awaited ability to multitask with iOS 4 that was first shown off when Apple announced the new version to developers. That means that finally, Skype can run quietly in the background, yet be able to receive calls or IM messages, as well as the ability to open other apps during those calls or chats.
However, one group of users has discovered that the promised multitasking simply doesn’t work on their device: Those who have jailbroken their handset to run any number of Apple-denied apps using Cydia or Rock, and particularly those who have unlocked their device. In their case, the app runs fine until it’s put in the background, at which time it closes the same way it’s always done, killing any activity that might occur while it’s closed (which include active calls).
The problem was noted almost immediately by user comments on Skype’s blog after the app update was made available, and the culprit appears to be Mobile Substrate, a hacker-written support framework which makes a lot of the popular Cydia apps such as WinterBoard and even the Dev Team’s Ultrasn0w unlock possible.
The first time Skype runs on a jailbroken device, the message above appears: “This version of Skype is only supported on unmodified iPhone OS 3.0.x, 3.1.x, and 3.2.x” (and yes, this message still appears even under iOS 4!). In the past, a jailbreak user could simply hit the OK button and the app would continue to run without incident.
This time, however, Skype appears to have killed the ability to work in the background under iOS 4, or something about the jailbreak is making the app appear to be running on unsupported hardware, since Skype notes that multitasking is only supported on the iPhone 4 and iPhone 3GS models (despite the fact that non-jailbreak iPod touch users have also been reporting it works fine).
We’re fairly certain that the jailbreak community will update the Mobile Substrate framework to address the problem as they’ve always done in the past, although there are scattered reports that even unhacked devices are also failing to work in the background, so it’s possible that the Skype app itself has an undetected bug. More on this as it develops!
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