Android unit without gravity sensor gets stuck with screen rotated I have an Android unit which does not contain a gravity sensor.

It should always be in Landscape mode, but when I open certain apps
they force screen rotation to Portrait mode. After I go back to the
launcher however, the screen stays rotated to Portrait mode without
ever going back to Landscape mode, the way I want it to.

What can I do to make it always stick with Landscape mode? Is there 
som /system/build.properties  value that I can change or what can I
do? Is it because of the Launcher application itself?

I have (probably modified) Android version 4.2.2
Some apps only work in portrait mode due to the fact that that is the way they are designed. Also most launchers (on a phone) are automatically in fixed portrait mode as well. If you don't have a gravity sensor then I suggest using an app like Unlimited Rotation Control which puts rotation buttons on your device. For landscape mode on my phone I installed Nova Launcher and turned the rotation option on in the settings. There are also multiple launchers out there that can work as well however.