Comparison

a vs JS Shell

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

a

This app provides a local Unix terminal emulator for iOS devices, enabling users to run various Unix commands, edit files, and process data. It includes support for multiple programming languages and network utilities, with integration for iOS Shortcuts and multi-window functionality.

Highlights
  • Local Unix terminal emulator
  • Run Unix commands
  • File transfer (scp, curl)
  • Text editing (vim, ed)
  • Programming languages (Python, Lua, C)
  • Network utilities (ping, nslookup)
  • iOS Shortcuts integration
Features
Read full description

a-Shell is a complete local terminal emulator, allowing to run most Unix commands on your iOS device. You can transfer files using scp and curl, edit them with vim and ed, process them using grep, awk and sed. You can work with git repositories using lg2.  Most commands are compiled for iOS native Arm64 format, making them fast and well integrated with the BSD Unix that powers iOS/iPadOS. a-Shell includes Python, Lua, Perl, JavaScript, C, C++ for programming and TeX (texlive 2025, with Tikz and LuaTeX) for text processing. There are also multiple network utilities: nslookup, ping, whois, ifconfig... Type help for help, help -l to get the full list of commands. a-Shell can be controlled from Shortcuts: run commands in order, process files in a-Shell, get the results as text or files, transfer files to other apps... a-shell uses iOS 13+ “multiple windows” ability, so you can run multiple shells at the same time, with different commands, in different directories. You can edit a file in one window with vim and process it in the other with python. Compile your C or C++ programs to webAssembly using clang or clang++, and execute the resulting binary. A complete webAssembly SDK is included (WASI-libc). a-Shell is the complete version. If you need a smaller app, and you don't need a C compiler, a TeX engine, or numpy and matplotlib, there is a-Shell mini.

About

JS Shell

Features
Read full description

JS Shell is a pocket-sized developer console that lets you write, run, and test web code (HTML, CSS, JavaScript) directly on iOS and macOS. No Xcode, no laptop, no remote server. Paste a page in, tap run, and it loads in a real WKWebView served from a local HTTP origin. A real secure-context origin on iOS, so modern web APIs — from WebRTC to Geolocation — behave the way they should. KEY FEATURES Local HTTP server. An in-process server bound to the loopback interface. Provides a real secure-context origin so modern Web APIs work out of the box. Not reachable from outside the device. JavaScript REPL. A full JavaScript runtime backed by JavaScriptCore. Type js to enter the REPL. console.log, fetch, setTimeout, setInterval, Promises, and async await are all available. Real Promises, real microtasks, real JSON parsing, real URL parsing. Geolocation support. Test navigator.geolocation on a real iOS device. Permissions are handled by the system, just like Safari. Useful for validating location-based web features without deploying to a server. Persistent file system. Files you paste live in your Documents directory and survive app restarts. Each downloaded package gets its own directory. iCloud backup picks them up like any other app data. SQLite key-value store. A real B-tree on disk via SQLite. Read and write from your pages with same-origin fetch. No CORS configuration required. curl. A subset of curl built on URLSession. The flags X, H, d, i, I, o, A, m, v are supported. Pretty-prints JSON responses and saves binary blobs to the virtual filesystem. Archive extraction. In-process tar, tar.gz, tgz, gz, and zip extraction. No shelling out. Download a release tarball with curl, extract it, and run it immediately. Voice commands. Tap the mic, speak a command. Apple Speech framework converts speech to text. Auto-submits on detected silence. Voice commands are saved to the scripts list for one-tap re-run. Saved scripts. Save any sequence of commands as a named script. One-tap to re-run later. Voice-recognized commands are auto-saved to the scripts list for instant replay. Mac Catalyst support. Runs natively on macOS as a Mac Catalyst app. Multi-window, resizable, fullscreen-capable. The same code that runs on your iPhone runs on your Mac. DESIGNED FOR DEVELOPERS JS Shell is a tool for people who want to test web code on a real iOS device without installing Xcode, syncing files, or setting up a tunnel. It is especially useful for: Testing geolocation, camera, and microphone permission flows on iOS. Validating fetch, CORS, and cookie behavior on a real iPhone. Building small offline web tools that need persistent state. Running JavaScript snippets without opening Safari Inspector. Debugging mobile rendering edge cases on the device itself. PRIVACY JS Shell does not collect any user data. There is no telemetry, no ads, no analytics, no third-party SDKs, no remote configuration. Everything you type, paste, or download stays on your device. The local HTTP server only listens on the loopback interface and is not reachable from any network. The app forwards camera, microphone, speech recognition, and location permissions to web pages you load, exactly like Safari does on macOS. The first time a page tries to use them, iOS shows the standard system permission prompt. The first time a page tries to use them, iOS shows the standard system permission prompt.

Screenshots

a4 screens
JS Shell3 screens

Verdict

The call

The clearest difference is chart position: a at #22 against JS Shell's unranked. a also leads on iOS requirement (15.0 vs 17.0). On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Scorecard2 real differences · 9 level
a versus JS Shell: the parameters behind the verdict, then further details
ParameteraJS Shell
PriceFreeFree
Rating4.6 (570 ratings) — better—
Positive reviews78.4% of reviews—
Number of ratings570 — better—
Update frequencyMonthly—
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
Best chart rank#22 — better—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.0 — better17.0
Further details — not scored
Size2.1 GB6 MB
Age rating17+17+
DeveloperNicolas HolzschuchJowb Inc.

Bugs and requests

a

Reported bugs

3 issues
  • Toolbar buttons not accessible in portrait mode on some devices
  • Pasting from clipboard can insert unexpected characters
  • Sourcing certain script files causes crashes

Requested features

5 requests
  • Add support for package managers like Homebrew or APT
  • Implement more advanced shell features like job control and better tab completion
  • Integrate Git for version control
  • Allow installing additional packages and libraries
  • Improve clipboard and file management integration

JS Shell

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

a

No in-app purchases

None

JS Shell

No in-app purchases

Questions

Is a free?
a is free to download, with no in-app purchases.
Is JS Shell free?
JS Shell is free to download, with no in-app purchases.
Do a or JS Shell have ads?
Neither a nor JS Shell shows ads.

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