I'm a hobby photographer and I carry a gigantic phone. It's a Samsung S22 Ultra. With the case it's like 8" by 3". Time after time I find a nice jean pant, khaki, etc, and the pockets squirt out my phone while resting during a hike. And I have to retrace my steps. Ugg.
I also mountain bike. I've ordered all my long-leg mountain bike pants online as no bike store in my vicinity bothers to stock ladies mountain bike wear. Bummer. I've ordered three pairs of bike pants. They are okay, but not ideal. I've ordered mens and womens styles. None of them keep my legs warm, hold my phone reliably, or are attractive.
I found out about the Christa DIY on a Facebook ladies mountain bike group. A rider recommended these. It has a pocket for some sort of tool that is perfect for my ginormous cell phone. Yay!!
These are comfortable, good looking and secure my phone completely. I can do a handstand, and the phone stays put.
The photo I took is the tag in the tool pocket that holds my phone.
This pant is my holy grail.