First I want to be clear I do love my S4 and there is no way I would ever get rid of it. Now the lag on S4...
As I have posted in other posts yes I experience lag. And I turned off animations and disabled certain bloatware. That actually helped a lot believe it or not, but only with home screen, opening and closing an app. Now I still experience lag. But it isn't something I can't deal with. Previously I had all the iPhone lineup except 5, the Note II, and Droid DNA. Maybe its carrier bloatware that causes the lag, and maybe that's why certain people on certain networks don't have lag. I am on Verizon and I definitely see a lag comparing to the Droid DNA. And it didn't become obvious till you run certain apps like games. 2 games I ran that I play most frequent is Jetpack Joyride and Temple Run 2. The lag is very obvious when I run these games. I compare the smoothness to the DNA and I see there is no lag at all in the DNA. When I play Temple Run 2 on the S4 it stutters massively and lags. I can see an obvious skip sometimes and cause me to tumble to my death. I swipe and it takes a good second for my phone to react. Is this a big deal for me? No not really. Would I ever get rid of the phone? No, bc certain features of touchwiz is outstanding, such as the S-Calendar and widget for it. It is my daily productivity app.
My sense is that eventually this lag issue will be addressed accordingly. It may take a bit of time I'm sure. I always remind myself that initially release of a product especially technologies, always have glitches, it can be big and it can also be small. iOS also have its fair share of issues. The only reason that the glitches is very minimal is bc the software itself has been improved and built up for years and every iPhone uses the same exactly OS. Every release basically only comes with a few new features while most are enhancements to existing software. Touchwiz is still fairly young at this stage in comparison to iOS. I'm sure given enough time this issue will be a thing of the past.
Sent from my Galaxy S4