I gotta try that with my Galaxy S3, if I can still find it  

I've always let the electronic units run down to near out or until they beep at me.
The problem with about every one (cell or tablet) is that after about 2 years a noticeable drop in hours always happens.
What I have found actually caused the most problem, is that I get into the habit of plugging them in when I get home from work without even looking at the battery level.
Batteries develop a "memory" of charge/usage, sometimes you can break that chain by simply just letting them die. Just keep a charger with you (although sometimes that is not possible) for emergencies.
LOL, the deal with new phones is that they come out with a "new model" every year! and most are designed to only last two or three  years. I have an old nokia that still stays charged for three or four days! (I used to keep it in my truck for a 911 phone)
Most of the issues i've had more than batteries was that the headphone jacks would go from stereo to mono, become static ridden, or just plain stop working. When blue tooth started getting cheaper, I would change to a wireless headset after the plugs would go.
I still have a motorola razor that works just fine, except the frequencies aren't supported anymore......sigh..... sometimes technology improvements just aren't improvements.