As you can see from the screenshots below, they would allow to change the backlight, the number of notifications to be displayed (four or six), the activation delay, the style of the screen, add new apps (still very few) to the usual three and have an extended view of events in program.
Actually, they appear to be only screens without management code, since nothing seems to work, except for the debugging settings in the fourth screen. Those actually affect the backlighting of the screen and the white tone of the characters (but could simply be related to the variation of backlighting).
As for the gesture, there are activities (not working) to activate the gesture on the fingerprint reader, to manage the virtual navigation bar (these should not affect the Nokia 8, since it has capacitive keys) and to switch from rear camera to front and viceversa with a double twist (in this case it's an empty activity with only the title, for this I don't put the screenshot):
They could simply be stock code residuals, but for the gestures on the fingerprint reader there is the animation of what appears to be a Nokia 7 (or one of the new Nokia 7 Plus and Nokia 8 Sirocco or 9), while for the gesture to emulate the navigation keys, I've never seen similar ones. From animations and descriptions it's clear that, when you hide the navigation bar, you can go back with a swipe upward in the bottom left; to home with a swipe upward in the bottom center and a swipe upward on bottom right for recent apps (iPhone X style ).
Finally this seems to be a screen to choose a different color profile, but it doesn't seem to work, so it may very well be a residual stock software not implemented:
I found these activities in the Android 8.1 beta for Nokia 8, I don't know if they are also present in the stable build of Android 8. It seems that something is actually in development, like the Glance, while the rest could be customizations for the chinese ROM of the Nokia 7, or maybe something in the making for new devices cooming soon.
If you want to browse or find other "news", it's all reachable by creating shortcuts to these activities using the appropriate Nova widget. You can find these among the System UI and Settings activities (.keyguard.glance.testing.GlanceSettingsActivityFo rTesting, .keyguard.glance.PrimaryNotificationIndicatorsSett ings, .keyguard.glance.NotificationIndicatorsMainSetting s, .keyguard.glance.GlanceStyleSettingsActivity, .Setting$DoubleTwistSuggestionActivity, .Settings$SwipeToNotificationSuggestionActivity, .Settings$SoftkeySettingsActivity, .Settings$NavigationBarSettingsActivity, .Settings$ScreenModeActivity) .
If you decide to take a look, pay attention to what you do, because starting certain activities could make the device unusable. For example, by starting the activity of FQC, a tool used to test and approve the units in production, it will be extremely difficult to exit, the shutdown and forced reboot of the device is also inhibited (hmd should remove it from the final software, but if I'm not mistaken, it was also present in the stable build of Android 8).
Do it at your own risk.