How to save battery on android devices without using applications

It is now difficult to make it to the end of the day with the phone still charged. This is due to our almost continuous use of applications that consume a lot of battery. Here are some tips to save battery:

Lowering the screen brightness

Battery consumption is mainly caused by the screen, so I recommend you use automatic brightness or keep it at a very low level.
If you are in very bright places it is better if you use light backgrounds that enhance the contrast with the text, so you can keep the brightness at a lower level.

Eliminating widgets and live wallpapers

Animated wallpapers and widgets, while aesthetically very beautiful, consume a lot of battery because working in the background they cause a higher energy demand by the processor.

Activating app power saving

Via settings> battery you can view the battery consumption of your phone. This can be used to choose which apps have the greatest impact and then intervene.
From these settings you can also activate the energy saving of the apps. You can choose to activate it always or only if you do not use them for more than a certain time (which you can decide at the top right).
Attention: if you activate energy saving some applications may not be able to able to send you notifications.

Activating power saving mode

To save money you can activate the "power saving" mode which, however, will make your phone slower and less responsive.
In extreme cases you can use the "advanced power saving" mode: uses a simple layout, grayscale screen and allows you to use only essential applications (including Whatsapp).