I have an iPhone 5 and I have noticed that some days my battery depletes faster. I use the same apps everyday and I have the same usage pattern. Yesterday my phone showed 91% battery left. I plugged it in the charger for about 20 minutes and it showed that my battery was 100% charged. Three hours later, I had 60% battery left. My question is, even though it shows that it is 100% fully charged, it might not be? I found that very weird. I shut my phone off every night before going to bed and close all apps to make sure they are not running in the background. Any help to keep this from happening, will be highly appreciated.