If I am just using my eyes? the scrolling is still not as smooth and as instantly responsive as it is on newer iOS devices, you can feel and see it, granted its a Nexus 7 from 2013 with a underclocked quad core 1.5 ghz S600 SoC but still
It is smooth dont get me wrong, but iOS still a notch above in that department
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iPad air is most certainly more snappier and offers better responsiveness then the Nexus 7
And data encryption affects it because when the read/write speed cant feed the CPU and even GPU fast enough, switching between apps and things of that nature can stutter and not to mention the Nexus 6 launches games and depending on the app 2-3x slower then other Flagship Android devices (Note 4, M8, S5, G3 , etc)
sorry you're full of it.
GPU renders off RAM, not NAND memory. Same as the CPU. That's how computers work.
but anyway even assuming nexus 6 is relatively slow - it's definitely not noticeably any slower or any faster compared to the iPhone 6. (first hand experience by the way)