Look as a tech I tend to deal with issues like this often and find that changing my phone won't fix the problem. My note 4 would do weird stuff like battery drain in less than an hr. Come to find out it was a failed tower system of Verizon's. This is a whole different beast. It could be a combination of apps, signal fluctuations, what app was opened last, etc. I fail to see where I have 2 seperate days of crap battery life and my phone is bad. Then everyone on here with battery drain issues has a bad phone. Not likely. I have only had one bad cell phone ever and that was an HTC that the speaker was faulty out of the box. There is either a software issue with Samsung or they have remote access we don't know about.