I was just doing random stuff on my phone and went to click a button near the top right of the screen, and was mildly horrified to see "1%", so I immediately put it into the charger, where the phone promptly started showing "0%" for the next ~30 seconds. The phone never died.
Has this happened to any of you?
Measuring the amount of battery that's left is always a total crapshoot. I don't know for sure but I strongly suspect that they try to smooth over the phone's inability to tell what's going on by showing a gradual decline in the battery level regardless of what is happening, adjusting the speed of the decline as time passes depending on what vague and incomplete information it's able to gather about what it actually happening with the battery.