## 5 Major Equipment and Technologies
### Smartphone  
Although strong cellular communications coverage is lacking, cellular communications are the main communication methods in remote regions. Whenever a contractor is needed to update most agricultural communities, smartphones are a powerful communication technology and the primary method of communication. Recent advances in the smartphone industry have led to a sharp drop in prices, which has made the sector more attractive, especially for small farmers in rural regions. According to the global system assessment for mobile communications, this proportion is almost eight percent [74]. Moreover, features and flexibility, including GPS, microphone cameras, accelerometers, proximity, and gyroscopes, have attracted IT technicians who are creating more attractive smartphone functions to satisfy many demands of farmers [75; 76; 77; 78]. Due to advancements in the research, experts have developed various new tools and approaches strategically to implement smartphone technology in agriculture. Several developing countries, such as Ghana, Kenya, Nigeria, Uganda, Mali, and Zimbabwe, are adopting advanced tools and techniques in agriculture [79; 80; 81; 82]. Moreover, smartphone technology is used in many countries, such as China, Turkey, India, and several African  
Figure 4: The process of phenotyping. countries, which are listed above. These countries are implementing this advanced technology to increase agriculture production and boost their economies [83; 84; 85; 86]. The use of smartphones in the agricultural sector significantly depends upon numerous aspects. For this purpose, studies were conducted to determine smartphones' usage for several agriculture measures [87]. Table 1 presents the classification of smartphone-related sensors that have attracted experts to use them for different agricultural purposes. Table 2 includes some significant smartphone applications generated for numerous agricultural approaches, as well as their functions and applications. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Smartphone Sensors** & **Purpose** & **Common Agriculture Usages** & **References** \\ \hline \multirow{2}{*}{Image sensor (Camera)} & Take images of any object & Leaf area index (LAI), fruit ripeness, harvest & [87] \\  & Measures acceleration that used to & readiness, soil erosion, disease detection. & [88] \\ Accelerometer & observe the tilting motion and & Rotation of camera during use, machine & [88] \\  & orientation of the object & activities, or detecting workers. & [88] \\ GPS & Provides location, measuring the & Used for location information, land & [89] \\  & latitude and longitude of devices & measurement, and crop mapping & [89] \\  & Detects usual or unusual sound and & Maintenance of machine, detection of bugs, & \\  & transform into electrical waves & and making audio queries. & \\ Gyroscope & Senses the angular velocity to track the & Canopy structure measurement and & [89] \\  & target rotation/turn & equipment movement. & \\  & Utilizes accelerometer and gyro to & The precise distance of the plant, leaves, & \\  & determine the object altitude in relation & and/or any other object is measured from & [91] \\  & to the inertial system & the camera. & \\  & Barometer & Measure air pressure & Measure air pressure & [92] \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Uses of smartphone sensors in advanced agriculture. GPS: global positioning system.