I love flying the 787 and just before landing, I always calibrate my device so the plane won’t go crazy. It works with every other plane except the 787. If I calibrate on the 787, the nose of the plane with drop. I also tried on solo, putting my phone on the desk (which is flat) and calibrated but the nose of the plane will still drop.
iPhone SE
IOS 10.3.1
Not jail broken or modified
Latest version of infinite flight.
I dont know why you calibrate your device flat on a desk. I always calibrate my ipad holding it how I feel more comfortable at the very begining of the fly, then I use trim as needed for the rest of the flight. Never had an issue with any aircraft.