looks like this new stylus by wacom will work with iPad mini 4 and allow pressure sensitivity as it is advertised to work with iPad air 2 and must have solved the conflict with the touch id sensor
https://store.wacom.com/us/en/product/CS600C1K/?_ga=1.110235533.908696595.1442444652
(ipad mini 4 is probably not listed on the site because it was posted before it was released)
https://store.wacom.com/us/en/product/CS600C1K/?_ga=1.110235533.908696595.1442444652
(ipad mini 4 is probably not listed on the site because it was posted before it was released)