With the launch of the Realme GT 2 Pro and Realme GT 2, the brand has introduced a novelty in its fingerprint readers: heart rate recording. And we tested how well it works by pitting cellphones against a smartwatch and a medical blood pressure monitor.
Fingerprint readers in smart phones They’re designed to ensure secure access to the phone, but that’s not their only purpose: they double as buttons (the power button is common) and even gesture support on Android. What we never imagined is that a fingerprint reader could record a person’s heartbeat. This is precisely what Realme offers in its GT 2.
Heart rate measurement in Realme Lab
Realme UI, the manufacturer’s custom layer, includes experimental options which can be tested to take a look at what Realme is preparing for future updates. There’s “DC Dimming” to reduce screen flicker at minimum brightness, for example. And Realme UI 3 on the GT 2 also includes heart rate tracking.
Since phones that offer fingerprint unlocking with a sensor under the screen perform this function by capturing the light reflected from the finger using an optical sensor (with the exception of Samsung which integrates an ultrasonic sensor in its Galaxy range premium), Realme takes advantage of analyze the passage of blood through the finger and thus obtain the heart rate of the user. Something similar to the pulse measurement with the rear clera that Google Fit has created.
To use the curious method of analyzing heartbeats using the Realme GT 2’s fingerprint reader, the following steps must be performed:
- Open phone settings and scroll down to “Realme Lab”.
- Enter in “heart rate measurement“.
- Place your finger (any finger) on the fingerprint sensor (bottom of the screen) and hold it there for 15 seconds while reading.
The phone will save all readings in the “History” tab along with the time and date they were taken. Unfortunately, the heart rate measured by the mobile cannot be associated with any health application, nor shared. Therefore, the only way to export the data is to point it manually.
How accurate is the heart rate measured with the fingerprint reader?
We pitted the Realme GT 2 against heart rate reading from a smartwatch (Apple Watch Series 7) and a medical blood pressure monitor. The results were quite imprecise.: at rest, the pulses squared on the watch and the blood pressure monitor with measurements between 49 and 55 pulses; the Realme GT 2 ranged between 74 and 100 beats.
Since optical sensors are always more accurate at low keystrokes, the fingerprint reader shows such a large margin of error excludes its use for any consideration, including sports.
The measurement with the fingerprint reader is only a curiosity: its margin of error excludes any exploitation of the data
Out of curiosity, this seems to us to be a fairly successful option: it is a good complement to the secure unlocking of the phone. Too bad it varies so much, even from one finger to another. Also from person to person.
