[Fascinate Android Development] iofthestorm:
I'm an electrical engineer, and none of this makes any sense. V=IR is for current and voltage going through/across a constant resistor. Transistors are not constant resistors. The current through a Metal Oxide Semiconductor Field Effect Transistor (MOSFET), the type of transistor that is in basically all ICs, is always in positive relation to the voltage, at least for the purposes of this basic explanation. Decreasing the supply voltage, which is you can consider to be the VGS of a transistor for a simple analysis, is always going to decrease the current as well. Thus, depending on the range of operation of the MOSFET, decreasing the voltage will also decrease the current and thus power will decrease more than linearly. Less current means that the transistors will charge and discharge capacitances slower, and that's why you need voltages for higher clock speeds and overclocking IN GENERAL. Device physics is really weird.

Now, someone else was saying that maybe because you undervolt it less current goes through which means it needs to spend more time in a higher clock state. This is completely false, the current going through it has nothing to do directly with the amount of work done. Yes, you need more current for faster clock speeds, but at a given clock speed, it doesn't matter how much voltage or current there is and how fast the individual parts of the circuit work, as long as the longest delay in any part of the circuit is less than the clock rate. If it's longer than the clock period, then your circuit is no longer going to function and you'll have instability and crashes, but there is a bit of wiggle room designed into these circuits because each chip can be different. That's why you can overclock or undervolt a CPU, because obviously if it was designed to run at the fastest clock speed possible, any little variation in supply voltage, temperature, manufacturing process/lithography (which is very common) would cause your CPU to completely not function. You have to design your circuits to be tolerant of some amount of error from many sources (even cosmic radiation in some cases), otherwise it won't just be slow, it won't function at all. Logic circuits are clocked to synchronize data going through the circuit, and if the timing constraints aren't always obeyed you'll get wrong answers which would probably crash your OS. Undervolting will never cause the CPU to do less work in one clock cycle, unless you undervolt it too much, in which case things will likely blow up in your face.

Sorry for the wall of text, but hopefully this will clear up some stuff. And in the future, please stick to what you're good at and don't try to speculate things based on one formula that you heard sometime in physics while you were half asleep, or something some CSR told you to get you to shut up. Believe it or not, the people who are designing CPUs and writing/modifying kernels and operating systems actually know what they're doing and you're not going to suddenly realize that they're going about their business wrong because of something you learned in high school.

Edit: One other thing. The calculation of percentages of battery life is a bit of guesswork on the side of your phone, trying to determine via statistics what a voltage level means in terms of percentage of battery life. Battery voltages don't drop linearly as you use them, and can be affected by many things, such as whether it's plugged in to the charger in particular. That's why you see a drop immediately when you unplug your phone, and why looking at 2-3% differences is completely meaningless. The better way to test would be to actually see how long you can use it with an equal amount of work being done on each voltage, which is hard to do in real life. Too many variables are present in today's smartphones, what with background tasks and data coming and going and the like. And wireless radios are a huge battery drain, especially when you're receiving a weak signal. I would advise people to just carry a charger or usb cable with them and top up your battery when you need to rather than worry so much about small differences in battery life. You'll save on a lot of stressing ;).