This perhaps could be of interest to You @AmpBenzScientist .
A mobile phone or perhaps a smartphone with a li-ion battery lasting up to 1 month.
https://blog.flipperzero.one/1-month-battery-life-with-firmware-update/
@PawelK Infinitime had the same problem with the PineTime and its Nordic chip.
A cell phone would be very different. What Mr. Lee is working on could actually get closer to it if the Pinephone had a low power screen and a larger battery. There is likely a problem with that hardware revision too. It has enough control to where it charged at 5V 3A without issue for me. Two microcontrollers control charging of the device.
Just additional q from a noob:
Is much power lost in idle-running and/or unneedily high clocking of CPUs and/or specialized subcores like 3D-GPU and/or various radios?
@AmpBenzScientist
I would attempt on decoupling their clock controls, and/or adding more granularity per core visavis clocking selection and power level.
Also static display screens wouldnt need 1M refreshes per second.