* Phone computing

Smartphones are typically walled gardens, with few ways of running one's own
programs. However, on Android there exists a terminal emulator which opens up a
lot of opportunities, and which is the basis for my mobile computing; Termux.

Termux functions as a normal terminal emulator, so you can run any normal Linux
program on it. It comes with a package manager based on Debian's apt.

** Usage

The volume up and down keys correspond to holding down alt and ctrl
respectively. There's also many useful buttons present above the virtual
keyboard like the tab key among others.

** SSH server

I run an openssh server daemon on my phone to allow for file transfer between it
and my computer, as well as letting me run commands on it from my computer. It's
very simple to set up.

1. Run ``pkg install openssh`` to get the ``sshd`` binary.

2. Run ``sshd``.

3. Add your public key to the phones ``~/.ssh/authorized_keys`` file.

From here you can access the phone's files with ``sftp`` and run commands by
``ssh``'ing into it. You'll need the phone's IP address as well, which you can
get by running ``ip a`` on it (assuming you're connecting to it on the same
network). Remember that you need to login as the user on the phone, which you
can see with the ``whoami`` command.

** Accessing the rest of the phone's files

Termux has its own directory where it stores all your files. To access the other
files available on the phone like your pictures, music, etc. run
``termux-setup-storage``. This will create a symlink in your home directory to
the root of the phone's file system.

** The package manager

The package manager is very simple, and shares much of its functionality with
apt.

``
# Update the package repository
pkg update

# Update installed packages
pkg upgrade

# Install a new package
pkg install <package>

# Remove a package
pkg remove <package>

# Search for a package
pkg search <query>

# Some additional software repositories include root-repo, unstable-repo, and
# x11-repo. These can be installed with `pkg install':
pkg install root-repo
pkg install unstable-repo
pkg install x11-repo
``

One can also use apt directly, with its commands.

{https://archenoth.com/tech/2020/05/29/Roguelikes-in-Termux.html Roguelikes in
Termux}