I have some devices like an iphone which is all of 4 years old and going
on 5. I can use org-mode to log battery recharge and battery discharge
durations with a basic org-mode table and in the event the discharge
duration starts dropping off sharply maybe get to a store and replace the
phone. I put two inactive time stamps in a field for recharge and
discharge and beside both of those fields I have a duration field where I
do the math and record the hours and minutes.
I have an ~/org/logs/iphone.org file and have other directories under that
~/org/ directory too.
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