OkBattery Backup is good yes its decreased than earlier September month but nearly 9Hrs backup. You can update to Beta 1 it has no bugs you can feel better than stable because nothing always push Beta as Stable only don't wait for A15 Stable you'll get it after February 14th . Because beta 2 will be out on mid January.
Thanks for your review
But unfortunately i updated yesterday's 19 mb update now i am unable to update to nos 3.0 beta1.

Have to wait for stable nos 3.0 now