Polarized sunglasses vs iPad portrait mode

I use a mini 2 and have best luck with a brimmed cap and no sunglasses, both for seeing the screen and for seeing the inspire in the air. I always take my sunglasses off when flying and then put them back on after landing.
On my mini 2 the screen is just slightly darker in landscape mode with polarized glasses and that's the only orientation available to me in the app.