Ok. Iam going to be the one everybody says BS to. I have an S4 on US Cellular running 4.3. My battery will last 50 plus hours with normal usage. Normal usage for me is phone calls,texts,checking email,FB and Twitter with ocassional music or youtube. I have Battery Doctor app installed and I let it kill background running apps every 6 hours or so.My GPS is off,WIFI on all the time, I am in a 4GLTE area. The big thing I do not let the phone do is sync anything. I have to get my email,update FB and Twitter manually.I use the phone a lot for different things. I have the stock OEM battery nothing special. After I installed the Battery Doctor app my time when up by almost 24 hours. OK I know all this sounds impossible but I charge every 3rd day unless I am going to be when that is not possible. How is my phone getting this kind of hours on the battery I have no idea. My Nexus only got about 16 with the same apps and set the same except for the battery app,CM Security and Clean Master. all the other apps were on my Nexus. I carried 4 batteries for it. I do not yet own a spare battery for the S4. Now I like the rest have read about battery issues with the S4 but I just do not have them. My 4.3 was loaded around Nov 13 according to the date in the phone. I have not upgraded to KitKat as I have no reason to mess up a good thing. comments appreciated and questions answered if you want. I am just here to share and learn myself. Now to the Micro SD Card thread.