Just intalled the new OTA update. Now it seems that "Background task clear" can't be turned off anymore. Although it's switched to "Off", all background tasks are terminated as soon as the phone goes to sleep mode. No WhatsApp, no 3D parallax wallpapers, no push notifications, nothing.
As a workaround I switched "Background task clear" to "On" now and put ALL apps on the white list. Now everything works as before.
Oh, and I now have "system somatosensory" in the settings menu which wasn't called like that before.
Edit:
"Shortcut flashlight" not working anymore (turning on flash light by long pressing home button while on lock screen).