Arterial oxygen saturation ([Formula: see text]) is an indicator of how much oxygen is carried by hemoglobin in the blood. Having enough oxygen is vital for the functioning of cells in the human body. Measurement of [Formula: see text] is typically estimated with a pulse oximeter, but recent works have investigated how smartphone cameras can be used to infer [Formula: see text]. In this paper, we propose methods for the measurement of [Formula: see text] with a smartphone using convolutional neural networks and preprocessing steps to better guard against motion artifacts. To evaluate this methodology, we conducted a breath-holding study involving 39 participants. We compare the results using two different mobile phones. We compare our model with the ratio-of-ratios model that is widely used in pulse oximeter applications, showing that our system has significantly lower mean absolute error (2.02%) than a medical pulse oximeter.

Spirometry is the gold standard for managing and diagnosing obstructive lung diseases. Clinical spirometers, however, are expensive and have limited portability. Vortex whistles have shown promise as a potential substitute for clinical spirometers. While vortex whistles are low-cost and are highly portable, only a subset of common spirometry measurements can be measured reliably. Moreover, no research studies have evaluated characteristics of human interaction with vortex whistles, such as maneuver learnability and mental effort. We present a modified 3D-printed vortex whistle design that enables estimation of spirometry measures not previously attainable with traditional vortex whistles. We evaluate the whistle using a pulmonary waveform generator (a commercial standard) and map parameters of the whistle construction to spirometry test endpoints. Through a human subjects trial we evaluate how to personalize whistle parameters for different subjects and assess cognitive workload while using a vortex whistle. We show that, with personalization, vortex whistles are as effective as clinical spirometers for identifying moderate airway obstruction and require similar cognitive load to use.