Android Question While installation on Android 8.1 device no app folder created

Any errors during install? Do you find the app's icon and are you able to start it?

No errors, app's icon is here. If I start it, the first screen is displayed for less than 1 second. Than app is closed, because some files are not available: The app folder doesn't exist.

I uninstalled this app on another device with Android 5. With ES File Explorer I see all folders of the app are removed. Then install it again with B4A Bridge. All folders are here and the app works fine.

It seems is a problem with permissions write on external storage and no sd card is inserted.

The app files are private. No other apps (or explorers) can access these files.

You can save files on the secondary storage which is public. See the runtime permissions video tutorial.