It works on any A6 or below device running iOS 7, just not A7. It won't work for full customization, but it's decent enough to change the horrid stock icons to something to your liking.
I'm not saying that it doesn't work. I'm just saying that it's chews the battery up.
Also noticed while looking at CPU usage that it keep it pretty busy. When I uninstalled winterboard it returned to a normal CPU usage idle.
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I don't think just having winter board installed drains the battery.
Well it did for me.
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I will wait for it to be updated.
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If you run Mobile Terminal and TOP you should notice a higher average idle. It did for me. Hey maybe it's just doesn't like a 4S.