The smartphones (or smartphones) that we use today have nothing to do with those mobile phones that we used just a decade ago. On this day, but 10 years ago, Samsung launched the first Galaxy S, Apple presented its iPhone 4 with a 3.5-inch screen, HTC did the same with its Desire and shortly after the Nexus One arrived in stores.
But if we must mention a phone that, although it was not one of the best sellers of the year, it is a clear example of the designs that we may no longer find in most mobile devices, that was the Motorola FlipOut, a true square smartphone with rounded edges and a QWERTY keyboard that was hidden behind, appearing just at the moment when the screen was sliding.
Today our mobile phone has become a true feat of engineering. And, it is true, many of its best feats are found in the presence of a range of sensors that fully complete some of its main functions.
Gyroscope
This is a truly useful sensor, helping the accelerometer to understand in which direction the phone is facing , adding another level of precision to make 360-degree photos look truly spectacular, for example.
It is the sensor in charge of detecting what we are doing when we play a racing game and we tilt the screen to steer the vehicle, applying only small turns to the phone, instead of moving everywhere. And, interestingly, the first time they were introduced on a mobile phone happened on the iPhone 4, which went on sale in 2010.
At that time it was considered a true advance, since it helped to detect the orientation of the phone with absolute and clear precision.
Accelerometer
It is possibly one of the most important. They handle axis-based motion detection , and tell the phone’s software where it is pointing, in addition to tracking our steps when we walk with the device.
However, it has a rather interesting peculiarity: the sensor itself is made up of other sensors, including microscopic crystalline structures that act due to acceleration forces. The accelerometer then interprets the voltage coming from these crystals to determine which direction the phone is pointing and how fast it is moving. In fact, it is in charge of detecting and applying applications from vertical to horizontal , and vice versa.
Magnetometer
It is another of the sensors, along with the accelerometer and the gyroscope, that act by determining where a phone is in physical space. It is responsible for measuring magnetic fields and indicating in which direction north is by varying its voltage output to the telephone.
When we enter and exit compass mode within Google Maps or Apple Maps, the magnetometer is activated in order to determine in which direction the map should be. But more importantly, it works in conjunction with data from both the accelerometer and the GPS unit to find out which way you are and where.
GPS
The GPS positioning system is another of the important sensors that we find in our mobile phone. It uses a network of 30 satellites that orbit the earth continuously, which are connected to the smartphone to obtain a triangulation with the position of the device, using the position data obtained by at least three of them.
Thus, once connected with several satellites, it calculates where it is based on the intersection angles.
They don’t actually use any of the data on our phone, so even if we have lost coverage, we can still check our location, even if the map tiles are blurry and poor resolution.
Biometric sensors
Today almost all mobile phones that we find in stores will come with a facial recognition system or with a fingerprint sensor , useful to help us log into the phone. Even though they can be tampered with, they are generally considered safer and more convenient than just using a PIN code or a simple pattern lock.
There are three main types: capacitive (scanning with electronic capacitors), optical (scanning with light), and ultrasonic (scanning with sound waves).
Other useful sensors
We can also find other equally useful sensors. The proximity sensor is usually located near the top speaker and combines an infrared LED and a light detector to work when the phone is close to our ear, so that the screen can be turned off. To do this, the sensor is capable of emitting a beam of light that is bouncing, but invisible to the human eye.
The ambient light sensor takes care of measuring the light in the room and adjusting the screen brightness accordingly (as long as it is set to be adjusted automatically).
As with the rest of the technology that we find inside our mobile phone, the sensors are getting smaller and smarter, and they consume less energy.
