I believe the solution for you is Python-for-Android (Py4A). Not only does it allow you to run scripts on your Android device, but you can go one step further because the project includes simple draft instructions on creating a standalone, downloadable Android APK package.

First, I would start by going to the readme section of Py4A. There is a recipes (script) that will fit your needs. The python3 recipe allows Python3 to run as a "standalone" on Android.

This excerpt from Linux Journal explains script installation on your Android device:

Running on a Smartphone

To run a Python script on your physical Android device, install SL4A together with Python for Android on your handset, then transfer your script.

To install SL4A on your physical Android device, enable the Unknown Sources option in your device's Application settings. This setting is required to enable the installation of non-Market apps on your phone. With this done, you can follow the same steps you used when installing SL4A and Python on your emulator. To speed things up a little, install Barcode Scanner from the Android Market and use it to “read” the QR Codes from your desktop screen.

Transferring Your Script to Your Handset

There are a number of ways to get your script onto a real phone. I've found the success of using something like Bluetooth connectivity or USB cabling arrangements can very much depend on the hardware on which you're running. What works on one handset, doesn't on another, and so on. Your mileage may vary depending on your actual device. When I need to transfer a file, I've come to rely on a solution that works no matter which handset I use (as long as the handset can talk to a local Wi-Fi network). What I do is switch on the OpenSSH server on my development PC running Linux, then use the AndFTP file transfer app on the handset to scp files from the desktop to the phone. AndFTP is available from the Android Market as a free download and installs in minutes. Once I connect to my desktop with AndFTP, I can navigate to a directory of my choice, mark the files that I want, then download them to my SD card on the handset.

AndFTP works well, and I've come to depend on it for all my Android file transfers (see Resources). Just be sure to transfer your scripts to /sdcard/sl4a/scripts on the phone to ensure that your script names appear within the SL4A list of scripts.

With your script file transferred to your physical device, start SL4A as before, tap your app's name and tap the run wheel. As expected, your app runs just as it did on the emulator, only faster! I haven't included a screenshot of the app running on a real phone for two reasons. First, it looks exactly the same as it did in the emulator, and second, it's running on your device, so you can take a look at it there!

Creating an APK

There's one further kink to SL4A that might interest you. The project includes draft instructions on creating a standalone, downloadable Android APK package (see Resources). Once created, the APK file bundles your custom Python script with information that allows other Android users to install Python for Android automatically onto their handsets and then run your app from the smartphone's main menu of apps. Describing the process of creating the APK likely would take another article, so I leave it to the brave among you to try out the instructions on the SL4A Wiki"

Python-for-Android website.

OK it is solved. I followed these steps (http://code.google.com/p/python-for-android/wiki/RunPythonFromShell) but first I had to put the file standalone_python.sh in /data/ because in sdcard I had no permission to execute. And finally using 'su' I made it to run my script as root.

You can use the termux app, link to homepage, which is available in the google market and requires no root. It is a terminal emulator with a full Linux environment and via apt install python you can install python. apt list gives you a list of all available packages.

Even though the termux app hasn't been updated in over 2 years, I'd say it's still the best way to run the python cli on Android in 2024. As @Robert notes, the termux-packages repository on GitHub is still updated and provides package updates.

On a fresh install of Termux, the default bintray mirror is down and will need to be changed:

termux-change-repo
# use arrow keys and the space bar to select all 3 repos
# press enter and choose a different mirror

# Upgrade existing packages
pkg upgrade

# Install python
pkg install python

# Check python version
python -V
# 3.11.8

You could use UserLAnd, GNURoot Debian, or Termux. Termux is probably the most lightweight, and also has Swipe keyboard support (have to swipe the entire input to the side to access it), and you can enable an extended keyboard that pops up over whatever keyboard you use to access arrows, Tab, Ctrl, etc. UserLAnd also has the extended keyboard and the same Swipe support, and runs a full version of Linux in a chroot environment so you can have root access using sudo or the root user.

Using Termux & UserLAnd on an unrootable Android and both are amazing. rsync is the greatest thing ever to keep project changes up to date because AFAIK it's not possible to edit the data stored in either of their filesystems directly using an Android app, but can be done using vi/vim/nano/etc inside of Termux or in UserLAnd's session (have to connect to it through SSH or VNC).

Just make sure to follow the suggestions during UserLAnd setup and grab ConnectBot and/or bVNC -- those are currently the only supported apps to connect to it. Also, while it claims to be able to setup for a single app I have not seen any directions for that, and have no idea how it would be possible as the UI doesn't seem to have anyway to do so.

One way is to use Kivy:

Open source Python library for rapid development of applications that make use of innovative user interfaces, such as multi-touch apps.

Kivy runs on Linux, Windows, OS X, Android and iOS. You can run the same [python] code on all supported platforms.

Kivy Showcase app

I worked out the solution by going to the Python-for-Android (Py4A) home and found the script that allows Python3 to run as a "Stand alone" on Android.

There are 3 ways to do this:

• I created the "standalone.sh" script, saved it at "HOME"(export HOME=/data/data/com.spartacusrex.spartacuside/files), changed its mode to executable, called it and python appeared.

• I opened the ~/.bashrc and pasted copied in the code:

export EXTERNAL_STORAGE=/mnt/sdcard/com.googlecode.python3forandroid
export PY34A=/data/data/com.googlecode.python3forandroid/files/python3
export PY4A_EXTRAS=$EXTERNAL_STORAGE/extras
PYTHONPATH=$EXTERNAL_STORAGE/extras/python3
PYTHONPATH=${PYTHONPATH}:$PY34A/lib/python3.2/lib-dynload
export PYTHONPATH
export TEMP=$EXTERNAL_STORAGE/extras/python3/tmp
export PYTHON_EGG_CACHE=$TEMP
export PYTHONHOME=$PY34A
export LD_LIBRARY_PATH=$PY34A/lib
$PYTHONHOME/bin/python3 "$@"

Note that this means every time you launch Terminal IDE, you will automatically load Python and find yourself at the Python prompt.

• To launch Python the normal way, like shown by Lanky Cyril, paste the following code in the .bashrc:

export EXTERNAL_STORAGE=/mnt/sdcard/com.googlecode.python3forandroid
export PY34A=/data/data/com.googlecode.python3forandroid/files/python3
export PY4A_EXTRAS=$EXTERNAL_STORAGE/extras
PYTHONPATH=$EXTERNAL_STORAGE/extras/python3
PYTHONPATH=${PYTHONPATH}:$PY34A/lib/python3.2/lib-dynload
export PYTHONPATH
export TEMP=$EXTERNAL_STORAGE/extras/python3/tmp
export PYTHON_EGG_CACHE=$TEMP
export PYTHONHOME=$PY34A
export LD_LIBRARY_PATH=$PY34A/lib

You will notice that the last line in the second solution has been taken out and put in an executable file "~/python". Here is the code:

  #!/system/bin/sh   
  /data/data/com.googlecode.python3forandroid/files/python3/bin/python3 "$@"

I used the second one so that when I launch Terminal IDE, I get my Python prompt instantly. I installed the third solution so that, should I leave the Python prompt, I have a way to get back in the same terminal session.