Almost all of the Android smartphones have a built-in battery saver function that automatically kicks in when the battery level reaches 15%.

To maximize the battery saving, you can customize the trigger and set it to automatically enable when your phone’s battery percentage gets down to 30% or 25%.

To further save the battery juice, use these best free battery saving apps that are so much effective that they let you minimize the load on processor cores and lowers the CPU processing power.