Why does Landscape lock not always work ?

[androidgeek2019]

It appears that when Auto Rotation is switched off in landscape mode, some apps ignore that and the screen still rotares, which is very annoying.
I prefer landscape because computer and TV screens are also landscape and when viewing websites on the browser on my phone or viewing photos or videos, they are shown normally and not shown stamp sized in portrait.
For that reason I installed Rotation (the paid version) which works really good and keeps everything in landscape, except the lock screen. Since Android 8 Oreo the lock screen is portrait only by design, I don't know what is the reason of that, but I can live with that.
And my question is: why do phone manufacturers have such a preference for portrait mode while all other screens like TVs and computers use landscape ?

 

[GameTheory]

Sometimes it's as simple as the developer just wanting to make their app for a specific view mode. It takes additional planning and coding to support landscape in addition to portrait. Overall, portrait better suits a smart phone, especially for one handed use.

The lockscreen is just another app and is better layed out over portrait. ie Displaying album art looks better on portrait.

As for me, I prefer portrait for everything except video.

 

[puppykickr]

This is an old thread, but I ha e found a great free and ad-free screen orientation app that solves this issue.

It can lock your screen into any position, and forces any app to obey the same.

https://play.google.com/store/apps/details?id=com.pransuinc.screenorientation