CaliBattery

Battery info app with the manual voltage calibration.

It is actual for the device with a problem built-in battery info driver, showing wrong charge level. If your system indicator shows the battery charge OK - you do not need this app, no need to make negative review.

This utility can:
* get system's present voltage info of the battery (if the system returns it, it must be 4-digit value in milliVolts, usually 3400...4200, some device cannot do it)
* save the Max battery voltage you enter manually (when it's fully charged for sure)
* save the Min battery voltage you enter manually (when battery is just alive, discharged, say - just after switching on)
* calculate the battery charge % accoring to these voltage levels and show it
* notify, if battery (calculated) is getting low, and when is almost discharged (and must be pugged in for power source as soon as possible)
* save every hour battery charge statistics and show the graph chart
* optional auto-saving the min and max voltage, if it's smaller or exeeds the current voltage
* controlling the battery temperature
* shows average battery charge level, for several minutes (not moment)
* send data by email periodically: for remote controlling temperature. Calibration is possible - battery is several (3-4 degrees) hotter compared with room ambient temperature when Android is idle, and extra 3-4 degrees hotter when Android is powered up, charging. So some number can be deducted as the calibration value before sending.
NOTE: SMTP email server is stored encrypted.

* discharge speed (% per hour) calculation and the text alert, if exceeds the limit (option).
If charging from a power adapter - the value is negative.

* Experimental new function (paid option) - battery quality analysis (the possibility to bear the voltage drop at high load): switch the option on in the SETTINGS menu - the saving of charge and discharge stat (if no charger plugged in) will start. Use device several hours or days. STATISTICS menu can show the charts and analysis result, if battery quality evaluation is > 60% it's good, else the battery looks loosing its capacity.

* shows the rest life time evaluation as dd:hh:mm days:hours:minutes in the notification area, if the battery analysis option is activated (paid option)

NOTE: only Max and Min levels are correct, the linear calculated % values may differ from system's or other app's battery info, it's not a bug.
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Alarm minimal charge level is 40%, it is 5% after the registration (in-app billing payment by Google Wallet).

So, step-by-step:
1) Charge the device battery fully for sure (3-5 hours)
2) Start the application and make sure that the Present voltage is 4-digit value
3) Set the Max voltage by "Set present voltage" button under it
4) Set the Min voltage around 3200 mV or leave the default
5) Save the settings
6) Use the device until it switched off
7) Start charging and switch the device on and set now the Min voltage to the Present one
8) Save setting and try using your device checking the charge level.