Recently, I have been using the maximum power saving mode alot on my tab A7. I always used the medium power saving mode. It saved me around 10 to 15 percent battery everyday when compared to not using the power saving mode. One day I had only 15% battery left on my device and I did not have a charger around and I had to attend my online class that was for about 1 hr 10 minutes. It takes me about 15 percent for a class that is for 40 minutes but this class was for 1 hr 10 minutes. So, I decided to give the maximum power saving mode a try. I attended the class with still 4 percent left. So nowadays, when I do not have a charger handy I turn on the maximum power saving mode at around 80 to 90% battery only to be safe and still end the day with some charging left and it really does work. There are two ways to turn it on.
Battery and device care
Battery
Power saving mode
Maximum power saving mode
The steps to turn maximum power saving mode are-
1) Turn it on from notification panel
Or
1) Go to settings
2) Click on the 'battery and device care' option
3) Click on the 'battery' option
4) Click on the 'power saving mode' option
5) Turn on all the three options (Limit CPU speed to 70% + Decrease brightness by 10% + Limit apps and home screen)
6) Turn on the 'power saving mode'
Note: It is only necessary to turn on the last option that is Limit apps and home screen to turn on maximum power saving mode. To save the most battery turn on all of the options.
These are the pictures of the steps-
Process 1)
Process 2)
