JS Shell vs Multiplex

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.

Multiplex Remote keeps you connected to the terminal and Coding agents like Claude code sessions running on your Mac, from your phone. Pair your iPhone with the Multiplex app on your Mac and pick up any running session: watch live output, type commands, and respond the moment Claude Code needs your input. TERMINAL, WHEREVER YOU ARE Every paired session is a real terminal, mirrored from your Mac in real time. Scroll back through history, use the on-screen arrow keys and modifiers, or fit the output to your phone's width for readable text on the smallest screens. NEVER MISS A "NEEDS YOU" MOMENT Get a lock screen Live Activity and a notification the instant a Claude Code session is waiting on you, so you can approve, answer, or steer it without opening your Mac. GIT, WITHOUT LEAVING THE SESSION Open the built-in git inspector to browse changes, diffs, commit history, and branches for the repo your session is working in. PRIVATE BY DESIGN Your session reaches your phone through a relay that only ever routes opaque traffic between your own devices. Pairing uses a one-time code shown on your Mac and confirmed on your phone. Requires the free Multiplex app on your Mac.