Apple explains ‘jelly scrolling’ with LCD technology limitations

Apple provided explanation for 'jelly scrolling' effect which was noticed by some iPad mini users.

In response to our inquiry, Apple has told us that the "jelly scroll" issue on the 6th-generation iPad mini is normal behavior for LCD screens. Because these screens do refresh line by line, there is a tiny delay between when the lines at the top of the screen and lines at the bottom are refreshed. This can cause uneven scrolling issues like the ones observed on the iPad.

Ars Technica