Arrow Key Navigation on iPad External Keyboard Sometimes Causes Cursor to Jump

The Problem

I am using a Logitech K480 Bluetooth keyboard with a 7th generation iPad (iPadOS 14.6) and I often notice that when I am navigating a body of text I have typed (e.g. in the Notes or Facebook apps) with the keyboard arrows the cursor will jump to the beginning of a text field if I push the up arrow twice in a particular location. It can be quite annoying when trying to navigate text I’ve typed; it’s difficult to intentionally navigate using it (or avoid it) because of the variable length of lines in paragraphs.

The first push of the up arrow will move the cursor one line up and then the second push will jump the cursor; it happens both immediately and if I wait. If I push the down key after the jump (again either immediately or if I wait), the cursor will jump back to the original line (i.e. the line I was on before I pushed the up key the first time). The cursor jumping behaviour will occur again in the same manner when pushing the up key twice.

This behaviour consistently occurs if the cursor is at the end of a line following the first up arrow push, no matter the location of the paragraph on the page or the position of the line in the paragraph.

Related Behaviour

There is some related behaviour. When using Command + left arrow to skip to the end of the line, pushing the up arrow will consistently not move the cursor to the line above but will instead jump the cursor to the beginning of the same line (pushing the down cursor subsequently will jump the cursor back to its original position at the end of the line). Sometimes when navigating a typed document with the arrow keys, a push of the up or down arrow key seems to move two lines at once.

Possible Explanations

Together these behaviours and their consistency make me think this is an iPadOS ‘autoscrolling’ function, analogous to how deleting text with the onscreen keyboard speeds up the longer the backspace button is held. However, I have not found any documentation of this behaviour by Apple or anywhere else online.

I don’t think this is a feature of the K480 keyboard; it is not listed anywhere in the Logitech documentation, and the responder to my enquiry to Logitech seemed to have no knowledge of this phenomenon (though it was a particularly unhelpful response…). My work’s IT manager thinks it is likely an iPad software feature.

Perhaps this is just a feature of Apple devices that I’m not aware of (e.g. something that’s shared between Macs and iOS devices), but it is strange that I can’t seem to find even a mention of this behaviour.

The Questions

Has anyone else observed this behaviour? Can it be customised or toggled? Is there some documentation (or personal experience) of the behaviour that lays out how it works?