The moment we switch to other app , the previos app pauses there
Why is it so ??
Depends on the app.
That's precisely the way it works. Only a few apps such as Music can work simultaneously.
iOS 4- Understanding multitasking
Apps have to be coded to make full use of multitasking - a lot of older apps haven't been changed. Some apps you'd want to pause anyway e.g. games, videos etc.
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