I started out with a fully charged battery (100%). When I made my initial post, the percentage of the battery left was about 79% with the Android system accounting for 51% of the usage and that was after just one hour. At most, I used Pandora for 2.5 hours, but it was NOT a continuous 2.5 hours of usage. Towards the evening hours when I was on my way home, there was a period of about 30-45 minutes where my data service was basically non-existent. Knowing that the data wasn't working, I closed Pandora hoping that would save the battery until I could get to an area where I had service again but that didn't really help. So, I got a total of just under 4.5 hours out of the battery. Even if I am not using Pandora and instead briefly open the web browser to look at things throughout the day, the Android system still uses a good part of the battery.