Hi, I finally had a chance to use the app in an area with map coverage.
I have “dim between turns” enabled. I found that it worked as expected at first. After a few minutes of riding, the display seemed to get stuck in a “mostly dimmed” state - barely visible but not black. There was lots of ambient light - but not direct sunlight on the screen.
I manually increased the screen brightness to 100% (it was at ~25%). That worked until the c.t app dimmed the screen again. Then the screen stayed at about 25% brightness again.
I will try again tomorrow after restarting the phone. In the meantime I thought I would check whether anyone else observed this behavior.
iPhone 14 Pro, iOS version up to date, battery was not low, and low power mode was not on.