If you want to learn ethical hacking or networking with help of android devices then an application available for you called termux. termux is AN emulator for android mobiles that gives terminal emulator.we can use this terminal as Kali Linux terminal.
This Termux app accessible on Google play store thus you'll simply download it once the download and installation open termux app.Now 1st time this app shows you installing process so keep patient.
This process takes minimum 1 minute or less.Now you have termux terminal. In termux there is lots of packages are present we can install any package.
Installation method is similar to Kali Linux Terminal.Now you can run any Kali Linux commands.You can also install some basic requirements packages such as python, Perl, git, PHP, curl, ruby, etc., using this command :
apt install [package name]
If you would like to clone or download some tools/scripts from GitHub for Penetration Testing.Then you guys will simply clone some tools supported by termux emulator.
In this blog you guys can find basic to advance level guide and also termux tools tutorials, Termux penetration testing, Termux basic commands, Termux networking, Termux vulnerability scanning+detecting, Termux security tutorials, Termux scripts and many more.