OK, what cr6 said above is correct. I also know for sure that the rate which the phone charges not only changes based on what level of charge you already have but also "cycles" up and down almost constantly while Fast Charging. Ditch the app you downloaded and instead install
Ampere - Android Apps on Google Play. Then, connect the charger and watch... It will start out testing the charging rate, then begin to display the rate of charge at that moment, as well as a low number (min), indicating the minimum rate it has charged at since it started, and will also show a high number (max), which is indicating the maximum rate it has charged since starting.
As you watch it you will see that the rate it's charging will change almost every second or so then pause for a few seconds then we'll start changing again almost every second or so and this continues on and on through the entire charging process. That way I can go anywhere from 250 milliamps all the way up to over 4,000 milliamps of power and usually ranges between 700 somewhere in the order of between 700 and about 2500 mAh.
There is almost no possibility that its charging rate will be different based upon which house you're plug into. All houses in the same geographical region are supplied from the same power grid, and so they're all receiving approximately the same voltage at the same time. The voltage determines the charge rate, and so even though you will see the current or milli amperes, mAh changing. It's the voltage that dictates how much charge and how fast the battery is taking that charge. The battery will only take as much as it can handle at a certain voltage rate, but the charging rate is measured in current or mAh.
Each time you restart it, the high and low limits reset.
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