The experiment takes readings from the accelerometer's z axis and plots them in a histogram. Artithmetic mean and standard deviation are calculated and used to overlay a normal distribution on the historgram.
Note that bins are created in the given bin size from the minimum to the maximum value acquired so far. There is no limiting function, so if you have a small bin size of 0.001m/s² and shake your phone to measure values in the range of +/-10m/s², your phone will create 20000 bins, which can slow the interface significantly.
We suggest to use the "timed run" from the main menu to gather properly distributed data points while the phone is resting.
Also note, that depending on your device, the distribution might not really be a normal distribution but also subject to digital binning. In combination with the binning for the histogram, you might see weird effects as bin ranges overlap with different numbers of digital bins, resulting in few bins to significantly exceed others.