Originally Posted by jova33
With the newer phones it seems they're doing more with less. Meaning the processors work way better and use less juice. The S4 has a 2200 or 2400 mAh battery, and will last all day, where my GNex would only last 4 hours on 2100
Does your Gnex have an extended battery? If not it only has an 1800mah battery. The S4 has a 2600 mah battery. That's 800mah more than the Gnex, or nearly 50% more battery life.
In other words, if your Gnex lasts 12 hours on battery, the S4 should last 17 hrs 20 mins. A significant time longer, assuming similar power draw.