This is my experience: the TouchWiz that lags and affects performance is caused SOLELY by the TouchWiz launcher. When I replace the TouchWiz launcher any performance hit is completely, let me write that again,
completely...gone. I've used a ton of phones, including dry flavorless Nexus devices. Most recently (spelled last weekend) I really dove in and compared a Nexus 6 with Nova Prime to my Note 3 and Note 4 with Nova Prime. The 3 phones felt the same in launching apps, screen transitions, etc. and the Note 3 is an older design. I found I still don't care for the look of stock android and its stoic dry font and menus. Lollipop? You may keep it. Forever. No, really.
I've been replacing the TouchWiz launcher with Nova Prime or something else since the S3 and that's why I could never understand why people say Samsung devices lag.
Now, why in the world would anyone that knows better keep the performance affecting TouchWiz launcher when there is Nova, Apex, Aviate, ADW, Go, Next, etc that perform better and are way more flexible?
YMMV but, again, in my experience it is SOLELY the TouchWiz launcher that affects performance, not its underpinnings.
• from the i6+
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