Ditch the "Battery Calibration" app. Do the "METER CALIBRATION" (Not Battery Calibration), the way the manufacturer intended.
Power the phone off.
Charge to 100% with the Stock Wall charger (which should also be done with ANY NEW PHONE BEFORE USING).
Power the phone on.
Use it till the phone says "Low Battery" and tells you to plug in.
Power the phone off.
Charge to 100% with the Stock Wall charger.
Continue as normal from here forward.
Repeat this process above once every 2 months or so.
Also NEVER...let me say that again, NEVER let the battery drain to 0%, or "run it dead" unless it's totally unavoidable because you are being followed by a known criminal and you need to call 911 to report it. But seriously, running your battery to "dead" does NOTHING GOOD, and can only do from Minor to MAJOR BAD! With a battery meter that is out of calibration, as many become during the upgrade from Gingerbread to ICS, or after repeated charge/discharge cycles that over time throw off the meter of an otherwise normal phone and perfectly fine battery, the phone won't know what the proper voltage levels are to accurately predict the low battery threshold and prevent deep-discharging the battery.
Discharging your battery to "dead" or 0% and allowing the phone to self-power-down both causes undue stress to the battery which WILL contribute to a shortening of the battery's usable lifespan, and you also run the risk of inadvertently deep-discharging the battery and throwing yourself into a bootlooping situation, or worse, White Light of Death, where the phone will not take a charge at all, even with the Stock charger.
I ask you simply, would you let your car run out of gas?? If not, then why do so with your phone (not to imply that the two have any similarity in technology or purpose, mind you)? The battery meter is meant to warn you in due time of impending doom (dead battery), so that you can take proper action to either power the phone down normally, or to find a power source and at least partially replenish the battery's charge levels.