There are a few things that you can do to make your battery last a little bit longer. The basic things that you must do before anything is to just watch the battery. Just enable the battery percentage so you can have a little more information. This can be found in settings in battery. While we are here, you might check for unnecessary running apps. If there are some, tap on them and touch Force Stop.
Next, you should reduce the battery consumption. Not using the Bluetooth? Just turn it off. Same goes for everything, Wi-Fi, GPS, Data connection, etc… You might also want to decrease the backlight timeout and the brightness of the display.
Next on the list is charging. For optimal battery life, you should really use the Samsung USB/charging cable and wall charger that was included with your device. Just don’t use third-party chargers. If you are not in a hurry, plug your phone in your pc. Standard PC USB port has 1A. This will slowly charge your phone, but the charge is more thorough. When you are in a hurry you can use the wall charger or a fast charger. Typically, they have 2A current and charge the device quicker, but it tends to lose that charge more quickly.
If you are just running out of battery before you get home by the end of the day, you should consider enabling Power Saving Mode. This works by limiting CPU performance, reducing brightness and turning off key light and vibration feedback. You can set it on manually, or to turn on when the battery is less than your desired percentage.
For the extreme cases when you really need to save the some juice, you will want to turn on Ultra Power Saving Mode. This mode switches the device to grayscale and turns off unnecessary applications. Location and data connectivity will also be turned off.
For example, if your Galaxy S7 has 10% charge left, with Ultra Power Saving Mode it will last for up to 24hours and it will enable you to can make, and send and receive texts.