Battery Care and Feeding for Tablets, Phones, and other "semi-retired" devices used as dashboards

The idea here is to replicate what all laptops do to preserve battery life. Here are my notes, as I dug through several mountains of uninformed drivel and useless/malware apps to find these valid options.

The "Chargie" app is the an expensive, but "no fuss" way to go.

If you have a bootloader-unlocked device, you can run ACC (Releases · VR-25/acc · GitHub) and AccA (Releases · MatteCarra/AccA · GitHub). These allow directly powering the device and bypassing the battery entirely. If the device loses power, it will then
revert to battery.

If you have not unlocked the device then you can use Tasker and AutoInput.

Install Tasker/AutoInput, then slog through "setup", "accessibility", and "write secure adb" configurations. Both apps do a decent job of leading you by the nose on this.

Create two Tasker profiles with state = power and source = AC.
Toggle Invert for one of the profiles.

The Invert profile turns on the plug when your battery drops too low.

The 2nd profile turns off the plug when the battery is charged to a specified charge level.

Link your profile active when power is on (AC not Inverted) to the task that turns off when the battery hits 70%.

Link the Invert profile to the one that turns on when the battery hits 30%.

There ya go. Here is a link to tasker tasks that do as stated above, and can be a starting point for your own config. Download with any android device.>70%2C+OFF

Easier to type link -


This looks interesting, but only works with USB-A ports?

Very interesting and insightful. I wonder if one could use Tasker and a Tasmota plug? I.e. Turn the plug off and on when needed.

Certainly one could, but I did not want to waste a smart plug on a tablet not worth what the smart plug costs me! Engineering is the art of doing for 50 cents what any damn fool could do for a dollar.

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Unless you’re NASA or the military. :joy:

John Glenn, astronaut of "Friendship 7" (a Mercury capsule on an Atlas rocket) is said to have quipped when asked "how he felt" as the countdown progressed:

"I felt exactly how you would feel if you were getting ready to launch and knew you were sitting on top of 2 million parts — all built by the lowest bidder on a government contract."