Root not required
Ok so I just got an S5, mainly because I like bitching about Samsung (that and the major issues my note 3 had)
Keep in mind these methods will work for most phones, not just the S5, but all the options may not be available or in different locations. This guide is going to give you general tips and device specific tweaks to ensure that your phones battery get better performance without needing to root, or turn off all of the features of your phone. This guide also wont tell you to install this app or that app, just use your system.
So let's start with basic tips:
1. Your Screen
Ok so the number one killer of smartphones? The screen. The solution, keep your screen dimmed. When you're outside and its sunny, turn your body so you're in the shade and keep it low and at night you can pretty much have it turned down. This will drastically increase battery performance
2. Disable/Turn off Bloatware
Seems like a no brainer, but often over looked. The way Android is designed to effectively open apps quickly and multitask is that applications are constantly running. To help with battery performance, Android 4.1+ (can't remember if 4.0 can) has the ability to Turn Off or Disable applications that don't let you uninstall without root (they are in system/apps) to disable you go into Settings--> Application (Manager) and select the system apps you want to turn off and then choose "Turn Off". While you're in there, pay attention to the force close option. Later in phone use over time you can close out of applications so they won't stay running. I commonly force close apps that I don't use very often. Now this can be done with an android task manager a lot easier, but why add more bloat crap to your phone?
3. Limit Processes
This is the not so common tweak I actually just discovered which prompted me to make this post. In the developer options of your phone, there are some nice options in there that can help with battery life. Newer Android versions dont have the Developer Options enabled by default. To enable the Developer options, follow the following steps:
Settings-->About Phone--> Repeatedly tap on "build version" until there is a message that developer options is enabled. In your settings list, you will now have developer options in your settings list.
What to choose to help battery life in developer settings
》Check the option to "Do Not Keep Activities"
》Choose "Limit Background Processes" and select what you want to limit it to.
These options will slow down the opening of applications, but the overall performance and battery life will be improved.
Now for S5 (and some options for S4/S3) specific ways to increase battery life.
TURN OFF THE SHIT YOU DON'T USE!!!
For example, motion and air view settings. If you don't use them, turn them off. These gimicky features aren't needed and you can select and choose what you want to disable.
Disable things you are not using from your notification bar. If you're not using GPS, disable it. If you're not using Bluetooth, disable it. If you're not using WiFi, disable it.
I think you get the point. With these settings applied, enjoy a smartphone that's not constantly dying.
If you have ideas that can improve this guide, please share them and I will gladly update the OP
