Set Battery Saver Always On On Android 6, the battery saver automatically turns on when the battery is low and off after charging. I would like it remain on all constantly without having to manually turn it back on. How can I do this?
If you're using an unrooted Android, you can consider using BatterySaver Lollipop Shortcut with Tasker (userguide), AutoShortcut and Nova Launcher.

Fire up Tasker and follow these instructions:


Profile: Event &rarr; System &rarr; Intent Received:


Action: android.os.action.POWER_SAVE_MODE_CHANGING
Priority: Highest

Task: (Actions): 


Task &rarr; If &rarr; Condition: %mode eq false
Task &rarr; Wait &rarr; Seconds: 1
Optional: Alert &rarr; Flash &rarr; Enabling Battery Saver
Plugin &rarr; AutoShortcut:


Configuration: Activities (next to Nova launcher's icon) &rarr; tap Battery Saver entry and select the entry listing the activity com.fd.batterysaver.ToggleActivity


Profile: State &rarr; Power &rarr; Power:


Source: Any
tick Invert

Task: (Actions):


Optional: Alert &rarr; Flash &rarr; Enabling Battery Saver
Plugin &rarr; AutoShortcut &rarr; 


Configuration: Activities (next to Nova launcher's icon) &rarr; tap Battery Saver entry and select the entry listing the activity com.fd.batterysaver.ToggleActivity




You can use QuickShortcutMaker in place of Nova Launcher. However, I noticed that when Nova Launcher was not set as default launcher in my stock Android 6.0.1, although Settings app reported Battery Saver mode being enabled, I didn't get to see red shade in status bar and navigation bar. You may have to do some experiments here.

If you've root access, instead of using a shortcut to that battery saver app, you can setup the action Code &rarr; Run Shell and enter the following in the command field:

settings put global low_power 1


Make sure to tick Use Root in that action. (I came to know about this trick from this answer of Paweł Zmarzły.)

Whether the Android is rooted or not, the pro version of Battery Saver Lollipop claims to provide support for automation. It might be helpful considering that the free version causes few glitches during toggle. I cannot confirm though. 



Information about said Tasker profiles

Alright, so the first profile would make sure that as long as the device is not plugged in to any power source, whenever you would disable Batter Saver mode, whether accidentally or deliberately, the mode would automatically be turned on!

The second profile would make sure that Battery Saver mode gets turned on whenever the device is unplugged from  a power source.