This is my first full run in of my 1520 after a couple of days of charging. I found this battery app that gives comparable stat info to Android and downloaded it this morning before starting a full day of use. So, I downloaded the app, topped up the charge and started my day of no charger at 7:38am. I left the "Glance" feature on (this keeps the lock screen on with the current time and gives me notifications, weather and battery info with a quick glance). Screen is always at full brightness. No battery savings turned on. I tethered my iPad for 5 hours on a weak cell signal. Used Nokias Here maps for 1 hour and 15 minutes. Played a 90 minute video pod cast. Surfed the web, checked email, made calls and played a few games. This is a normal day for me and usually got around 3 to 4 hours of screen on time with the Nexus 5. The 1520 got juuuuuust a tad bit more.