Real-world 4G experience with the latest Android Galaxy Nexus:
Here’s the crazy part: when I am actually using the 4G network for tasks — such as turn-by-turn navigation or video streaming — it will drain 1-percent or more of battery life per minute.
Now, the Galaxy Nexus takes about 90 minutes to charge from 0 to 100-percent when plugged into the wall. Thus, when using 4G data while plugged into the wall charger your battery is basically treading water. If the phone is plugged into a less-powerful power source (such as a USB hub or a car charger) then using 4G will actually drain your battery faster than the power source can charge it — though it will not drain at the same one-percent-per-minute speed.
Earlier this week I spent some time driving around Kansas City in order to field test the turn-by-turn navigation, the LTE network, and the battery life. At 11:30 AM I started out and the battery of the Nexus was at 43-percent. After 25 minutes the battery had drained down to 33-percent even though it was plugged into a car charger.
4G is the best feature you’ll almost never use.