Table 1.

Reference and smartphone sensor properties.

Property	Reference	Smartphone 1	Smartphone 2	Smartphone 3
Sensor maker	PCB Piezotronics	ST Micro-electronics	ST Micro-electronics	Bosch Sensortec
Sensor model	393B04	LIS331DL	LIS331DLH	SMB380
Phone maker, model & Operating System (OS)/Data Acquisition (DAQ) model	NI SCXI-1531	iPhone 3GS, iOS	iPhone 5, iOS	Samsung Galaxy S4, Android
Type	Piezoelectric	MEMS	MEMS	MEMS
Sensitivity ± 2 g	1000 mV/g	18 mg/digit	1 mg/digit	3.9 mg/digit
Measurement range	5 g	2 g	2 g	2 g
Output data rate/Frequency range	0.05–750	100, 400	0.5–1000	3000
Noise density $\left(mg\sqrt{Hz}\right)$	0.00004	N/A	0.218	0.5