Which App Runs Code on Android? Python, Java, C++ Offline

If you want one app that runs code on an Android phone without a laptop or an internet connection, Pocket Compiler: Run Code runs Python, JavaScript, HTML and SQL offline from the moment you install it, and Java for free after a one-time download. C, C++, PHP and React are part of Pro. This guide compares it honestly with the other common choices so you can pick the right one for what you write.

The short answer

You want to type code and tap Run, in several languages: Pocket Compiler: Run Code (Google Play).
You only write Python and want a dedicated Python IDE: Pydroid 3.
You are comfortable on the command line and want a full Linux-style environment: Termux.
You want a code editor, not a runner: Acode.
You want a cloud workspace you can open from any device: Replit (needs internet and an account).

How the main options compare

App	Languages that run	Works offline	Account needed	Notes
Pocket Compiler: Run Code	Python, JavaScript, React, HTML, SQL, Java, C, C++, PHP	Yes (each extra language is a one-time download)	No	Editor, program input, GitHub clone, built-in terminal
Pydroid 3	Python	Yes	No	Dedicated Python IDE with pip and prebuilt packages; ads plus a premium tier
Termux	Whatever you install with `pkg` (python, clang, nodejs and more)	Yes, after installing packages	No	Free and open source; command line only
Acode	None built in (HTML preview)	Yes	No	Free, open-source editor; running Python or Java needs plugins or a terminal
Replit	Many, in the cloud	No	Yes	Code runs on Replit's servers, not on the phone

What Pocket Compiler does

Runs code on the phone. Write code or open a file, tap ▶ Run, and see the output or the error and the line it came from. Tap an error to jump to that line.
Reads program input. Programs that use input(), scanf, cin or Scanner work: you type the input, then run.
Shows HTML as a live page and SQL results as a table (a real SQLite database on the device).
Installs Python packages from a requirements.txt, including numpy and pandas (3 installs are free, then Pro).
Works with GitHub. Browse any public repository, clone it and run it (5 clones free), and save a file as a Gist.
Has a terminal with git, python, node and sqlite3, plus everyday commands like ls and cat. SSH to your own server is Pro.
Needs no account. Your code is stored and run on your device.

What it does not do

Free runs stop at 5 seconds (20 seconds with Pro), so it is meant for exercises, scripts and experiments, not long-running jobs.
C, C++, PHP and React need Pro on Android. On iPhone and iPad the app runs Python, JavaScript, HTML and SQL only.
It is not a full Linux distribution. If you need arbitrary system packages, Termux is the better tool.
The free version shows ads.

How to run your first program on Android

Install Pocket Compiler: Run Code from Google Play.
Create a new file and pick a language, for example hello.py.
Type print("Hello from my phone").
Tap ▶ Run. The output appears below the editor.
If your program reads input, type it in the input box first, then run again.
Try another language: create index.html to see a live page, or query.sql to see a results table.

Try a ready-made program

Our YouTube Shorts on @pocketcompiler show a short code on screen, like AI1. Type it in the app and that program opens, ready to run. AI1 is a tiny neural network written in about 60 lines of HTML and JavaScript, with no libraries (see the code page).

Frequently Asked Questions

Can I run code on Android without internet?

Yes. In Pocket Compiler, Python, JavaScript, HTML and SQL run offline from install. Java, and the Pro languages, need one download, then they run offline too.

Is there a free app that runs Java on Android?

Pocket Compiler runs Java for free after a one-time download. Free runs are limited to 5 seconds each.

Do I need root?

No. None of the apps in the table need root.

Does my code get uploaded?

Not in Pocket Compiler: your code is stored and run on your phone. Only if you choose to use the optional COSMO AI (Android, 18+) is the code you send passed to Google's Gemini API to explain or fix it.

Is Pocket Compiler on iPhone?

Yes, on the App Store. On iPhone and iPad it runs Python, JavaScript, HTML and SQL.

More details, screenshots and the full free-vs-Pro list are on the Pocket Compiler page.

~/cosmovex/untitled.md unsaved

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Meanwhile, the toolkit

~/cosmovex/home.md · rendered with Markdown Editor & MD Viewer

A Markdown editor good enough to write its own homepage.

This page is a Markdown document. You're reading the rendered preview — press or hit if you don't believe it. That round trip — plain text in, a clean document out — is what Markdown Editor & MD Viewer does on your Android phone. Free, offline, no account.

markdown Live Server — 2 editors, 1 file

# Two cursors, one document
My phone is hosting this file over Wi-Fi,
and my desktop is ed
> nothing leaves the device — it's your Wi-Fi, your file

▶ Install free on Google Play★ 4.7 on Play · 10,000+ installs · free

## New in v1.5 — watch it work

✓Version History — every save snapshotted; browse and restore

✓Works offline — no account, no cloud — files stay on your device

## Just shipped

Both offline-first, both free to try.

NEWAspenote: Offline Voice to TextIt writes it down. On your phone.Runs Offline · Nothing Uploaded · Summary & Actions

NEWHostPilot: PHP Server & SQLTurn your phone into a web server.PHP 8.4 & SQLite · Stays Running · SQL Console

## The rest of the toolkit

One app per job. No 200 MB do-everything bloat.

App	Job	Rating
Markdown Editor & MD Viewer	Write and preview Markdown on mobile.	4.7★ · 5K+	install ios
WebEva: Build Websites & Code	Build websites from your phone.	4.4★ · 5K+	install ios
PDF Viewer & Editor - AI	Edit, convert & sign PDFs on mobile.	4.9★ · 1K+	install ios
HTML Viewer & Editor - Code	View & edit HTML on mobile.	4.6★ · 1K+	install ios
SQLite Editor & SQL Learner	Manage SQLite databases on mobile.	5.0★ · 1K+	install
Python IDE - Offline Compiler	Write and run Python on your phone.	4.1★ · 1K+	install
Aspenote: Offline Voice to Text	It writes it down. On your phone.	—	install
HostPilot: PHP Server & SQL	Turn your phone into a web server.	—	install
DevBuddy: Offline Dev Toolkit	Your pocket developer toolkit.	—	install ios
ShellPilot - Batch SSH Client	SSH terminal & SFTP on the go.	— · 1K+	install ios
API Client -REST & HTTP Tester	Test APIs anywhere, anytime.	— · 500+	install ios
JSON Editor - Viewer & Format	View, edit & format JSON instantly.	— · 500+	install ios
Java & Kotlin Compiler IDE	Write and run Java on your phone.	4.4★ · 1K+	install
XML Viewer & Editor	View, edit & validate XML on mobile.	— · 5K+	install ios
Open CSV — Viewer & Editor	Open and edit CSV files on mobile.	— · 500+	install ios
JavaScript Editor — React IDE	Run JavaScript and React on your phone.	— · 1K+	install
Image to SVG Converter, Viewer	Convert images to SVG and edit vectors on mobile.	— · 1K+	install
YAML / YML Viewer & Editor	View, edit & validate YAML instantly.	— · 500+	install
Network Toolkit: WiFi IP Tools	Network utilities and diagnostic tools.	— · 500+	install
Code Editor - Text & Notepad	Edit text files on mobile.	— · 500+	install
C / C++ Compiler IDE	Compile & run C and C++ on your phone.	—	install
Diagram Maker: Flow & ERD	Draw flowcharts & ERDs on mobile.	—	install
QR Scanner & Generator	Scan codes with confidence	—	install
Zip Extractor — Unzip RAR 7Z	Open ZIP, RAR, and 7Z files	—	install
PromptCrate: AI Prompt Manager	Your personal AI prompt library	—	install

## Free web tools

Background Remover Snapglow SQLite Viewer QueryDrill

## Questions, answered

Is there a free Markdown editor for Android?

Yes — Markdown Editor & MD Viewer is free on Google Play. It gives you a split-view editor with live preview, syntax highlighting, and HTML/PDF export, and it works fully offline with no account.

Can I edit Markdown from my phone on a desktop browser?

Markdown Editor & MD Viewer includes a Live Server: your phone hosts the document over Wi-Fi and you edit it from any desktop browser with two-way live sync. The file never leaves your device.

Can I make Mermaid diagrams on Android?

Yes — the built-in Mermaid Studio turns plain text into flowcharts, sequence and class diagrams, with pan/zoom and SVG export, right on your phone.

Can I turn Markdown into slides or a PDF on my phone?

Presentation Mode turns any Markdown document into a fullscreen slide deck, and export produces styled HTML or print-ready PDF — all generated on-device.

## From the journal

We're a small studio with one rule: each app does a single job well, works offline, and never asks who you are.