That's interesting.
and this tester attaches or blue tooth to your smartphone??
It takes a pretty serious resistance in a circuit to load a battery.
I'm sure I'm not the only one curious about the tester.
I don't understand that first result as 'fail.' Wrong setting?
Some of the other guys here may have suggestions for verifying the multimeter's accuracy.
On some meters its better to probe for voltage differences between two points in the circuit. Better in that you can use a different scale. For example, measuring between the alternator Batt terminal and the regulator 'ignition' terminal with the engine running. On an analog meter you might switch it to the 5 Volt scale. On a digital, it might automatically change the scale/sensitivity.
The other advantage of reading the voltage difference directly is there is no math involved. ;)