I've gone over this too many times.
Lag as in slower transitions between screens ....between apps....between processes. Sense has it compared to vanilla android. As does blur and the other overlay.
Try navigating through your phone quickly compared to aosp and you find yourself wait a little longer for your finger to be able to make the next move successfully. If you are not the type to navigate quickly...you say....no lag. Its like split second difference but its enough to annoy me. And it IS there despite how many of you trying to justify your purchase or defend your purchase. So 100 more owners can say no lag....but it doesn't dismiss the fact that senseui and blur and touchwiz add lag to android os
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