Three items on your Samsung Galaxy tablet suck down battery power faster than a massive alien fleet is defeated by a plucky antihero who just wants the girl:
A bright display
Wi-Fi networking
Bluetooth
It takes a lot of power for the tablet to give you a nice, bright touchscreen, so don’t make the screen any brighter than you have to. Unless you want to charge your tablet all the time. If possible, set the brightness to Auto. That setting saves a lot of power because it adjusts screen brightness based on the light in the area.
Both Wi-Fi networking and Bluetooth require extra power for their wireless radios. The amount isn’t much, but it’s enough that you should consider shutting them down when battery power gets low.
Another item that can draw a lot of power is turn-by-turn navigation. This feature is found in the Maps app but not readily used on a tablet as much as it is on a smartphone.
If you do use the Navigation feature on your Galactic tablet, ensure that the tablet is connected to the car’s 12-volt power supply. An adapter can be found at any electronics or phone store.