When my Galaxy S7 Edge updated to Android 7.0 everything was well and I can listen to hours through my bluetooth speaker, sync my fit bit connect to my car, and just leave bluetooth on all the time and it never shows up on the list of battery users.
BUT -- when myGalaxy Tab S2 (internet onlt) which had behaved exactly the same way updated to android 7.0 it started draining the battery. Bluetooth was showing up on the list first by mega percentages, 2-3 Times the amount of the display which had previously been the big user.
So I started diddling around with suggestions from the web. Nothing made any difference. I even did a backup and factory reset and restore. Did not make any difference. I then did a factory reset with out the restore. Did not download any non included apps except Yahoo Mail and Play Newsstand. Did not change any of the default settings on the apps. Turned bluetooth on. No devices were connected. It immediately became the number 1 battery user. I turned bluetooth off and it continued to drain the battery even off.
It did not stop appearing top on the list until I charged the battery to 100% again. Since I have kept the bluetooth off. The battery stats have returned to normal with display as the main user and battery life normal. This is making me crazy.