Table 3.
Number and percentage of devices supporting a specific group of sensors, by year.
| Sensors | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | |
| Accelerometer (Acc), n (%) | 2 (67) | 5 (71) | 16 (53) | 40 (46) | 50 (41.3) | 37 (30.8) | 4 (11) | |
| Acc + 1 sensor, n (%) |
|
|
|
|
|
|
|
|
|
|
PPGa |
|
1 (14) | 1 (3) | 9 (10) | 11 (9.1) | 27 (22.5) | 10 (26) |
|
|
GPSb | 1 (33) |
|
2 (7) | 9 (10) | 15 (12.4) | 3 (2.5) |
|
|
|
Gyroscope (Gyro) |
|
|
1 (3) | 3 (3) | 9 (7.4) | 4 (3.3) | 1 (3) |
|
|
Magnetometer (Mag) |
|
1 (14) | 2 (7) | 1 (1) | 3 (2.5) |
|
|
|
|
Barometer (Bar) |
|
|
|
1 (1) | 1 (0.8) |
|
2 (5) |
| Acc + 2 sensors, n (%) |
|
|
|
|
|
|
|
|
|
|
GPS + PPG |
|
|
1 (3) |
|
7 (5.8) | 6 (5) | 3 (8) |
|
|
Gyro + PPG |
|
|
|
4 (5) | 5 (4.1) | 5 (4.2) | 1 (3) |
|
|
Gyro + GPS |
|
|
|
1 (1) | 2 (1.7) | 2 (1.7) |
|
|
|
Bar + PPG |
|
|
1 (3) |
|
1 (0.8) | 2 (1.7) |
|
|
|
Gyro + Mag |
|
|
|
2 (2) | 1 (0.8) |
|
|
|
|
Mag + GPS |
|
|
1 (3) | 1 (1) | 1 (0.8) |
|
|
|
|
Mag + PPG |
|
|
|
|
|
1 (0.8) |
|
|
|
Gyro + Bar |
|
|
|
1 (1) |
|
|
|
|
|
Bar + GPS |
|
|
|
2 (2) |
|
|
|
| Acc + 3 sensors, n (%) |
|
|
|
|
|
|
|
|
|
|
Gyro + Mag + GPS |
|
|
1 (3) | 3 (3) | 3 (2.5) | 2 (1.7) | 1 (3) |
|
|
Gyro + Mag + PPG |
|
|
|
4 (5) | 2 (1.7) | 3 (2.5) | 1 (3) |
|
|
Mag + Bar + GPS |
|
|
3 (10) | 2 (2) |
|
4 (3.3) | 1 (3) |
|
|
Gyro + GPS + PPG |
|
|
|
1 (1) |
|
6 (5) | 1 (3) |
|
|
Bar + GPS + PPG |
|
|
|
|
|
2 (1.7) | 2 (5) |
|
|
Mag + GPS + PPG |
|
|
|
|
|
1 (0.8) | 1 (3) |
|
|
Gyro + Bar + PPG |
|
|
|
|
2 (1.7) |
|
|
|
|
Gyro + Mag + Bar |
|
|
|
|
|
1 (0.8) |
|
| Acc + 4 sensors, n (%) |
|
|
|
|
|
|
|
|
|
|
Mag + Bar + GPS + PPG |
|
|
1 (3) |
|
3 (2.5) | 4 (3.3) |
|
|
|
Gyro + Mag + GPS + PPG |
|
|
|
1 (1) |
|
3 (2.5) | 3 (8) |
|
|
Gyro + Bar + GPS + PPG |
|
|
|
|
2 (1.7) | 4 (3.3) | 1 (3) |
|
|
Gyro + Mag + Bar + GPS |
|
|
|
|
|
1 (0.8) | 2 (5) |
|
|
Gyro + Mag + Bar + PPG |
|
|
|
1 (1) | 1 (0.8) |
|
|
| Acc + 5 sensors, n (%) |
|
|
|
|
|
|
|
|
|
|
All sensors |
|
|
|
1 (1) | 2 (1.7) | 2 (1.7) | 4 (11) |
| Total, n | 3 | 7 | 30 | 87 | 121 | 120 | 38 | |
aPPG: photoplethysmography.
bGPS: global positioning system.