Used Smartphone has sensors, CPU, Memory and data storage. Node-Red Programming tool is installed in the smartphone. So, it can be used as IoT server.

Prepare your smartphone

• Download an app called “F-Droid” from www.fdroid.org. This app lets you install other apps that are free and open-source.
• From F-Droid, install an app called “Termux.” This will let you access a terminal on your smartphone, similar to the ones you see in movies where hackers type lots of code!
• Also, install the “Termux:Boot” add-on, which will allow apps to run when your phone starts up.

Set up your smartphone as an edge gateway:

• Open Termux and type in some commands to update and upgrade its software packages. Think of this as making sure your phone’s software is up-to-date and has all the necessary features.
• Install an SSH server on your phone. This will allow you to connect to your phone from your computer remotely and control it.

pkg update && pkg upgrade -y

pkg install openssh # ssh package

passwd: *******  # password

• Type in more commands to download and install some additional software packages. These packages will help you set up a program called “Node-RED” and a database called “PostgreSQL.”

For remote access, you can use window shell as the below similar command

ssh -p 8022 u0_a149@192.168.45.246

in the termux, download and install the belows

pkg install wget nano python  # download, editor, python program

wget https://www.yifrend.co.kr/mobilestation/read.txt

wget https://www.yifrend.co.kr/mobilestation/db_start.sh

wget https://www.yifrend.co.kr/mobilestation/check_np.py

wget https://www.yifrend.co.kr/mobilestation/install_postdb.sh

activate downloaded files and load as the follows;

chmod +x install_postdb.sh

./install_postdb.sh   # auto installation for node-red, postgresql

chmod +x db_start.sh

./db_start.sh       # auto start postgresql

chmod +x check_np.py # operation check info mail.

Before execute, you should set the email configuration with nano editor.