There is also the new Android Scripting Environment (ASE/SL4A) project. It looks awesome, and it has some integration with native Android components.

Note: no longer under "active development", but some forks may be.

Yes! : Android Scripting Environment

An example via Matt Cutts via SL4A -- "here’s a barcode scanner written in six lines of Python code:

import android
droid = android.Android()
code = droid.scanBarcode()
isbn = int(code['result']['SCAN_RESULT'])
url = "http://books.google.com?q=%d" % isbn
droid.startActivity('android.intent.action.VIEW', url)

Pygame Subset for Android

Pygame is a 2D game engine for Python (on desktop) that is popular with new programmers. The Pygame Subset for Android describes itself as...

...a port of a subset of Pygame functionality to the Android platform. The goal of the project is to allow the creation of Android-specific games, and to ease the porting of games from PC-like platforms to Android.

The examples include a complete game packaged as an APK, which is pretty interesting.

As a Python lover and Android programmer, I'm sad to say this is not a good way to go. There are two problems:

One problem is that there is a lot more than just a programming language to the Android development tools. A lot of the Android graphics involve XML files to configure the display, similar to HTML. The built-in java objects are integrated with this XML layout, and it's a lot easier than writing your code to go from logic to bitmap.

The other problem is that the G1 (and probably other Android devices for the near future) are not that fast. 200 MHz processors and RAM is very limited. Even in Java, you have to do a decent amount of rewriting-to-avoid-more-object-creation if you want to make your app perfectly smooth. Python is going to be too slow for a while still on mobile devices.

Scripting Layer for Android

SL4A does what you want. You can easily install it directly onto your device from their site, and do not need root.

It supports a range of languages. Python is the most mature. By default, it uses Python 2.6, but there is a 3.2 port you can use instead. I have used that port for all kinds of things on a Galaxy S2 and it worked fine.

API

SL4A provides a port of their android library for each supported language. The library provides an interface to the underlying Android API through a single Android object.

from android import Android

droid = Android()
droid.ttsSpeak('hello world') # example using the text to speech facade

Each language has pretty much the same API. You can even use the JavaScript API inside webviews.

let droid = new Android();
droid.ttsSpeak("hello from js");

User Interfaces

For user interfaces, you have three options:

• You can easily use the generic, native dialogues and menus through the API. This is good for confirmation dialogues and other basic user inputs.
• You can also open a webview from inside a Python script, then use HTML5 for the user interface. When you use webviews from Python, you can pass messages back and forth, between the webview and the Python process that spawned it. The UI will not be native, but it is still a good option to have.
• There is some support for native Android user interfaces, but I am not sure how well it works; I just haven't ever used it.

You can mix options, so you can have a webview for the main interface, and still use native dialogues.

QPython

There is a third party project named QPython. It builds on SL4A, and throws in some other useful stuff.

QPython gives you a nicer UI to manage your installation, and includes a little, touchscreen code editor, a Python shell, and a PIP shell for package management. They also have a Python 3 port. Both versions are available from the Play Store, free of charge. QPython also bundles libraries from a bunch of Python on Android projects, including Kivy, so it is not just SL4A.

Note that QPython still develop their fork of SL4A (though, not much to be honest). The main SL4A project itself is pretty much dead.

Useful Links

• SL4A Project (now on GitHub): https://github.com/damonkohler/sl4a
• SL4A Python 3 Port: https://code.google.com/p/python-for-android/wiki/Python3
• QPython Project: http://qpython.com
• Learn SL4A (Tutorialspoint): https://www.tutorialspoint.com/sl4a/index.htm

Not at the moment and you would be lucky to get Jython to work soon. If you're planning to start your development now you would be better off with just sticking to Java for now on.

Take a look at BeeWare. It has grown significantly. It is awarded with PSF (Python Software Foundation) Education Grant.

Beeware's aim is to be able to create native apps with Python for all supported operating systems, including Android.

Official Website: Beeware

Github Repo: https://github.com/beeware

Check out enaml-native which takes the react-native concept and applies it to python.

It lets users build apps with native Android widgets and provides APIs to use android and java libraries from python.

It also integrates with android-studio and shares a few of react's nice dev features like code reloading and remote debugging.