Nonin True SpO2 algorithm is validated in 14 published clinical studies covering sickle cell, dark skin tones, and low-perfusion states, making it the reference oximeter for clinical trial data collection where accuracy claims must be documented. Bluetooth 4.0 LE transmits SpO2 and pulse rate to iOS and Android telehealth apps and third-party EHR platforms using the Bluetooth SIG Health Device Profile standard. Automatic power-off conserves the replaceable CR2032 battery for 1,500 spot checks, suiting telehealth kits mailed to patients for home monitoring programmes. Onboard 24-hour memory stores readings when Bluetooth is unavailable, synchronising the backlog on reconnect. Class IIa CE marked and 510(k) FDA cleared for OTC and clinical use.