Display brightness on Android override issue

[TilmanGuenther]

• KOReader version: v2024.04
• Device: Google Pixel 6

Issue

When I open the KOReader app, it overrides the device's currently set brightness and imposes its own. The brightness can then be adjusted with the "Frontlight" setting slider, however the issue is that it does not get as dim as the system brightness.

Specifically, the absolute minimum brightness setting on the KOReader brightness slider is maybe 25% or so of the native system brightness. This means that if I have my system brightness set to 0%, as I commonly do at night, opening the KOReader app absolutely sears out my eyeballs and is supremely uncomfortable to use.

I don't really see a reason why the android version of the app should even have a brightness override/slider on non-eink displays, but I would also be happy if the slider simpley covered the entire range of screen brightnesses available rather than starting at 25%

Steps to reproduce

Use KOReader on an Android phone (Google Pixel 6) and lower the system brightness to 0. Opening KOReader will raise the screen brightnesses and lock out system-side adjustment.

[Frenzie]

That's not normal behavior unless you already adjusted it previously. Try closing the app completely and not touching the setting?

[offset-torque]

Some Android ROMs reserve the lowest brightness levels to itself and doesn't allow 3rd party programs to go that low. And this allowed level is generally too high to be used at night. Low probability, but that might be the culprit. Can other reader apps (like Moon Reader) can go that low TilmanGuenther ?

[TilmanGuenther]

@Frenzie You were right that this behavior goes away if I kill the app, only upon touching the in-app brightness slider does it "lock in" again, and I need to kill the app to unlock it.

@offset-torque This is very possible... I downloaded the Moon Reader app and the minimum brightness there is brighter than the minimum brightness via the Android brightness slider (although I think the app "cheats" by overlaying gray at low brightness to imitate an actually dim screen).

The Moon Reader app solves this issue by having a toggle checkbox next to the slider that enables/disables forced brightness override. Might be a good solution beyond the workaround of just not touching the in-app brightness slider.