Dear JMNK,
in order to understand physics of oscillations try to use "Acceleration spectrum" from "Tools" choosing the number of samples 4096 (for the best frequency resolution). Normally there is an amortization of the oscillations which gives some (constant) increase of the period and corresponding width of the (single) resonance peak. Unfortunately I do not have "acceleration without g" on my smartphone and I cannot check the phyphox programs you are using.
Mikhail
in order to understand physics of oscillations try to use "Acceleration spectrum" from "Tools" choosing the number of samples 4096 (for the best frequency resolution). Normally there is an amortization of the oscillations which gives some (constant) increase of the period and corresponding width of the (single) resonance peak. Unfortunately I do not have "acceleration without g" on my smartphone and I cannot check the phyphox programs you are using.
Mikhail