**Appendix B**

This appendix presents the hardware scheme of the notification device for promoting healthy eating behaviors.

**Appendix B**

**Figure A1.** Hardware scheme of the smart device for healthy eating behaviors. **Figure A1.** Hardware scheme of the smart device for healthy eating behaviors.

As indicated in Section 3 the prototype developed to promote healthy eating behaviors has been equipped with a monochrome 0.96″ 128 × 64 OLED graphic display using the driver chip SSD1306 from Adafruit (Adafruit Industries Inc., New York City, NY, USA). The OLED display (U5 component in the schematic diagram) has been connected through a SPI 4-wire interface to the ESP8266-12E System on a Chip (U2 component). The ESP8266 also keeps an I2C two-wire serial communication with the tri-axial accelerometer + tri-axial gyroscope InvenSense MPU-6050 IMU (U4 component). These three components are supplied with a 3.3 V regulated DC voltage provided by the LF33ABDT-TR 3.3 V Low-Dropout regulator (STMicroelectronics Inc., Geneva, Switzerland) (U1 component). A low-cost TP4056 micro USB single-cell lithium battery charger with cut-off protection (NanJing Top Power ASIC Corp., Nanjing, Jiangsu, China) has been used to properly adjust the charging current supplied to the 3.7 V LiPo battery and to prevent its total discharge. The TP4056 is represented by the U3 component in the schematic diagram. As indicated in Section 3 the prototype developed to promote healthy eating behaviors has been equipped with a monochrome 0.96" 128 × 64 OLED graphic display using the driver chip SSD1306 from Adafruit (Adafruit Industries Inc., New York City, NY, USA). The OLED display (U5 component in the schematic diagram) has been connected through a SPI 4-wire interface to the ESP8266-12E System on a Chip (U2 component). The ESP8266 also keeps an I2C two-wire serial communication with the tri-axial accelerometer + tri-axial gyroscope InvenSense MPU-6050 IMU (U4 component). These three components are supplied with a 3.3 V regulated DC voltage provided by the LF33ABDT-TR 3.3 V Low-Dropout regulator (STMicroelectronics Inc., Geneva, Switzerland) (U1 component). A low-cost TP4056 micro USB single-cell lithium battery charger with cut-off protection (NanJing Top Power ASIC Corp., Nanjing, Jiangsu, China) has been used to properly adjust the charging current supplied to the 3.7 V LiPo battery and to prevent its total discharge. The TP4056 is represented by the U3 component in the schematic diagram.

#### **Appendix C Appendix C**

This appendix presents the hardware scheme of the notification device for promoting physical activity in children. It is a simpler hardware scheme than the previous one from Appendix A. It keeps the LF33ABDT-TR 3.3 V LDO regulator, the ESP8266-12E and the TP4056 lithium battery charger which correspond to the components U1, U2 and U3, respectively. There are no OLED display and no IMU in this hardware scheme. Instead, a 5 RGB LED array (component U4) with integrated drivers from Adafruit is connected to the ESP8266-12E through the GPIO2 pin to provide visual cues. Lastly, this notification device also incorporates a feedback switch button (SW3 component) connected to the GPIO5 through a pull-up resistor. It is used to provide feedback to the system so that the notification has been attended by the end users. This appendix presents the hardware scheme of the notification device for promoting physical activity in children. It is a simpler hardware scheme than the previous one from Appendix B. It keeps the LF33ABDT-TR 3.3 V LDO regulator, the ESP8266-12E and the TP4056 lithium battery charger which correspond to the components U1, U2 and U3, respectively. There are no OLED display and no IMU in this hardware scheme. Instead, a 5 RGB LED array (component U4) with integrated drivers from Adafruit is connected to the ESP8266-12E through the GPIO2 pin to provide visual cues. Lastly, this notification device also incorporates a feedback switch button (SW3 component) connected to the GPIO5 through a pull-up resistor. It is used to provide feedback to the system so that the notification has been attended by the end users.

*Sensors* **2018**, *18*, 271 18 of 21

**Figure A2.** Hardware scheme of the smart device for promoting physical activity. **Figure A2.** Hardware scheme of the smart device for promoting physical activity.

### **Appendix D Appendix D**

This appendix describes the questions asked to each evaluator and the scale used for each question. This appendix describes the questions asked to each evaluator and the scale used for each question.

	- a. Name a. Name
	- b. Professional background b. Professional background

#### 2. Prototype 2. Prototype

	- Perceived effectiveness Perceived efficiency a. For each category select a response (5pt discrete scale)
		- Perceived satisfaction Clarity • Perceived effectiveness
