This is my first adventure into Android since I went to iOS back with my 4S. I love my new S7. But one question I have is, I have had my phone for 3 days and my battery seems to be running down faster than I expected. When I look at the battery usage. The Android System is always first at 30% and Android OS second at 20%. Is that normal? It seems really high. I understanding it happening the first day as it is building files. But 3 days later?