Juno 4.1 is here — Python 3.13, an AI coding assistant, projects, a REPL, and native iOS APIs. Editing is free, running code is free to try — Pro is a one-time purchase.
Zero-setup Python IDE that runs your code offline, an AI coding assistant, and a developer toolbox — in a first-class citizen app for iPad and iPhone.
Juno is designed to cover all your Python coding needs, supporting both Python scripts (.py) and Jupyter notebooks (.ipynb) — a document format focused on applying Python to data analysis and computational science.
FREE FEATURES
- Navigate and manage files and folders, quickly preview documents and media
- Browse and edit Jupyter notebooks in a powerful, customizable notebook editor with beautifully rendered previews — editing is free
- Write and edit code sources, scripts, JSON, XML, and other text-based formats — one versatile editor for code and text alike, with syntax highlighting
- Add quick access bookmarks for file system locations outside the app's sandbox, or simply open documents in place
PRO FEATURES
Only one thing in Juno is Pro: running code. Even that is free to try — a generous trial allowance lets you run notebooks, scripts, projects, and the REPL before you buy. After the trial, running code unlocks with a one-time Pro purchase — not a subscription.
- Run Jupyter notebooks, Python scripts, and whole projects locally with the built-in Python 3.13 interpreter and a full suite of up-to-date, preinstalled scientific and data packages — entirely offline
- Explore interactively in a Python REPL — open a standalone prompt, or drop into it after running a script or project to keep exploring what it defined
- Search the variables, functions, and imports in your session with the Object Inspector — no need to print each one
- Open any folder as a project: file tree, multiple editor tabs, run any script, with a coding assistant aware of the whole project
- Keep side outputs — Preview, Browser, Console, Object Inspector — open as side-by-side tabs in an output sidebar
- View local web servers and HTML your code produces in a built-in browser with developer debug tools
- Long-running scripts and Jupyter sessions keep going in the background
- Automate with Shortcuts and Siri: App Intents run a Python file, run Python code, or open a file — pass arguments and files, capture output, and chain actions
- Leverage powerful data analysis, machine learning and developer tools: NumPy, pandas, Matplotlib, SciPy, Scikit-learn, OpenCV, LXML, and more
- Enjoy painless package management: install any pure Python package with an intuitive package manager
AI CODING ASSISTANT
The assistant runs on your key, not ours: add your OpenAI, Anthropic, or Gemini API key, and requests go straight from your device to your provider. You control what you spend and share — Juno never takes a cut.
PYTHON MEETS iOS
Reach native iOS APIs straight from Python with the built-in juno modules: clipboard, Keychain, device info, location, motion sensors, contacts, reminders, photos, sound, notifications, sharing, and Bluetooth. Show native alerts and pickers, present full-screen image, video, and web previews, or call into UIKit, Foundation, and any Objective-C framework via the Objective-C bridge.
PYTHON SCRIPTS
Python scripts are plain-text Python source code files with a .py extension. Juno lets you work on these with snappy, intelligent code completion, a console with full terminal emulator support, and a built-in media viewer for code-generated images, plots, web apps, and more — executed by the embedded Python interpreter, locally on your iPhone or iPad and completely offline.
JUPYTER NOTEBOOKS
A Jupyter notebook is a versatile document format that stores live code, markdown text, plots, images, and LaTeX equations in a single .ipynb file. Notebooks keep a record of every input and output of an interactive session, embedding rich output (HTML, images, video, plots) right in the document — a perfect playground for data analysis, machine learning, and computational science, and Juno makes working with them a breeze!
My main Jupyter environment is Anaconda on my Mac. I use GitHub to sync about 30 notebooks and their associated Python source files over to Juno (both on my iPad and on my iPhone) so I can give impromptu demos and make small changes and improvements no matter where I am. Over time Juno has matured and grown fairly robust. I’m especially glad that Python 3.10 support came out in May 2023.Alex Staravoitau responded quickly when I reported a configuration glitch in the new Python 3.10 release (the Bokeh plotting library required a different version of jinja2). He gave me a temporary workaround and within a couple of days got a corrected version out to the App Store.Juno is probably my most favorite app. It’s been extraordinarily useful. A strong five stars!
Work likes Jupyter Notebook; makes it easy to use Python on the iPad
CookieElle
I am a Bioinformatician and I use Jupyter Notebook and Python as part of my workflow. Every now and then I like to take a break from using my computer, and simply use my iPad Pro to write Python scripts. I really like this app as it suits this purpose. Juno works like Jupyter Notebook, with the markdown style, python console, and even the functional keys of “B”, “A”, “M”, when adding a new line below, above, and markdown that makes Jupyter Notebook easy to use. I haven’t had any issues with delays, crashes, or bugs. It works great, and to take things a step further, I would really like to see R included as a language for this app. There is definitely a need for it.
My Everyday Jupyter Notebook Client for Drug Discovery Research
outkrow
I work as a scientist at a large pharmaceutical company in Boston and this app has been my daily driver for analyzing data on my iPad as well as my Vision Pro for the last few years. It’s truly been a productivity game changer. Instead of lugging my MacBook Pro into the lab, or to a meeting, I can bring my iPad to document my experiments. I also use Juno on my Vision Pro during my long train commute which is amazing. Thanks for developing this app!
Couldn’t tell how bad it was until after paying; do not buy
iAdjunct
This is not an IDE, this is a notebook. I was able to open a directory from Working Copy… but the GUI is pretty bad. You can browse around the files pretty easily, but you have to “Open Python Source” to edit and/or run the script. This takes you to a new screen. If you want to switch to another file (since any program worth its salt is more than one file) you have to use a separate tab to open a file browser, go to the file, then “Open Python Source” in that too - which brings up a popup dialog which you have to interact with before it REPLACES the open file. To go back, you have to do that all over again. Furthermore, if your app uses asyncio and it has an exception which leaves the loop running, you have NO WAY to stop it other than quitting the app. This was a complete waste of $25.
Developer Response
👋 Hey—Juno only lets you work on individual Python scripts for now, but I am working on adding support for Python *projects*, i.e. entire directories of related files that you can open in tabs within the project. This is an ambitious project and a WIP though, and I don’t have an ETA at the moment I’m afraid.However, Juno already lets you open multiple Python sources in separate app windows on iPad, and the dialogue asking whether you want to create a new window will only appear once, and will remember your setting from then on.You should be able to interrupt a running asyncio script with the “stop” button—please ping me at feedback@juno.sh if it doesn’t work in your case (a minimal example would be very helpful!), and I’ll be happy to investigate and fix this.
What's New in Juno 4.1.4:
HTML files now open in a live web view: pages run their JavaScript and load their own stylesheets, images, and scripts. This update also fixes installing certain packages from source, moving files in the project tree, and a range of stability issues.
Juno 4 is our biggest update yet — here's everything new.
CODING ASSISTANT
– Code alongside an AI assistant in your notebooks and scripts. Bring your own OpenAI, Anthropic, or Gemini API key and stay in full control of your data and usage.
PYTHON 3.13
– The built-in environment now runs Python 3.13, with every bundled package — NumPy, pandas, SciPy, Matplotlib, OpenCV, and more — updated along with it.
NEW WAYS TO RUN
– Python REPL: run code interactively at a prompt — standalone, or drop in after running a script or project.
– Project mode: open a folder as a project with a file tree, multiple editor tabs, and a project-aware assistant.
– Object Inspector: browse the variables, functions, and imports defined in your session.
– Output sidebar: keep previews, the console, a browser, and the inspector side by side.
PYTHON MEETS iOS
– New juno modules reach the clipboard, Keychain, device info, location, motion, contacts, reminders, photos, sound, notifications, sharing, and Bluetooth — plus native dialogs, full-screen previews, and an Objective-C bridge.
– Run Python files and code from Shortcuts and Siri, and keep long-running scripts and sessions going in the background.
MORE
– A built-in browser for local web servers and HTML, with view-source and console-log forwarding.
– One editor for code and text, with syntax highlighting and the coding assistant for both.
– Faster package search, collapsible cells, auto-scrolling notebooks, a customizable keyboard toolbar, redesigned settings, and a wide range of fixes and polish.
Editing notebooks and files is now free. Running code is a Pro feature — and you can try it, and every other Pro feature, free before you buy.
Version 4.1.4
The developer, Rational Matter, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
Usage Data
Diagnostics
Privacy practices may vary, for example, based on the features you use or your age. Learn More
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
Seller
Rational Matter Ltd
Size
692.2 MB
Category
Developer Tools
Compatibility
Requires iOS 17.0 or later.
iPhone Requires iOS 17.0 or later.
iPad Requires iPadOS 17.0 or later.
Apple Vision Requires visionOS 1.0 or later.
Languages
English and 7 more
English, French, German, Japanese, Russian, Simplified Chinese, Spanish, Traditional Chinese