Check out pop up multiple window multitasking from Paranoid Android
Yes, Paranoid Android is both. But the developers are not happy with the current range of multitasking with the multiwindow feature found on Samsung, Cyanogen and Cornerstone. As Paranoid Android puts it, "We think these implementations suck and we want to get it right this time." Did they get it right? You can check out the video below to see for yourself.
The video shows the Paranoid Android multiple window effect on both a Nexus handset and an Android tablet. Notice how the notification shade is used in this process. The developers explain that the video shows less than 10% of the functionality of the program. If so, looks like this is worth keeping an eye on for the future. One thing is for sure. These guys don't lighten up when talking about the competition.
source: ParanoidAndroid via Engadget
"Everyone knows this is a highly wanted feature, people pooped their pants for hardcoded mms pop-ups for christs sake. they are buying Samsung plastic phones for whacky s-multiwindow."-Paranoid Android
source: ParanoidAndroid via Engadget
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