Palm rejection works very bad on my iPad Pro using Pencil. The view jumps 90% of the times I rest my palm. I think that it has to do with the double tap function for fitting the view.
This is by far the app that handles worst palm rejection of all that I use. It seems that it doesn't use Apple Pencil capabilities.
Another problem that I find is that the strokes are very irregular when you draw slowly. In the next picture you can see the same line drawed slowly (left) and fast (right). The irregularities diminish when you zoom the view. If you want to write some text you need to zoom the view a lot in order to avoid this problem.
Thanks for the useful feedback.
We are investigating improving the ink quality with the Apple pencil.
On palm rejection, can you confirm that you have the Active Stylus option turned on?
Open a page > hit "..." > verify this icon is orange
It happens fewer times when I have the Active Stylus On.
I think that the problem is the way I rest my hand. Sometimes I rest directly my palm on the screen and have no problems, but other times my pinky knuckle hits the screen a little bit before the palm and that's when the view jumps moving and zooming.
I've tried the same movement in other apps that handle very well palm rejection like Procreate and Concepts and found that they both work the same. They pan the view using two fingers instead of one. That way if my knuckle hits before the palm draws a stroke but as soon as they detect the palm just after, the stroke disappears (sometimes it fails and little strokes remain)
Most of the time I don't realize this because it happens under my hand. In Catchbook as soon as the knuckle hits the screen the view starts to move, and sometimes starts to zoom as soon as my palm is rested.