Unlabled app entries appearing in battery history. Suspicious? This morning I noticed weird untitled entries in my battery history, which I'd never seen before.  I'm also not sure why some rows were not showing the percentages. (When tapped on, the entry detail views show the percentages.) The entries have the same code/gear icon as the Android OS entry:

  
entries / detail / same icon as Android OS (click images for larger variant)

These aren't appearing in the last-hour view now, so it appears to be something that launched earlier, and then stopped. "Force stop" and "report" are grayed out in the detail views.

Is this suspicious? Is there some way of checking these further?

This is on a non-rooted HTC One M9 running Android 6.0
Did you install any app from Unknown sources,  i.e. downloading the apk and then installing? If yes, Can you see these apps in the Apps section in Settings of your phone? And if yes, is the uninstall button active? 

If not, this might be due to the administrator privilages this app has got. First, you need to remove administrator privilages from the app. i would recommend to download ES File Manager from Play Store and finding that app. Then try to uninstall these apps and see if these really have administrator privilages. And, if they have, remove them using ES File Manager only and then, uninstall the applications.

Hope, this works fine for you. Basically, these apps are downloaded with the .apk file you download from the unknown resources, get themself administrator privilages and start showing ads on your device.