a-Shell is the open-source on-device Unix shell for iOS. It runs locally on the device via the ios_system project, vim, grep, python, lua, git, basic Unix tooling, all sandboxed inside a single iOS app. It is free, it is well-loved, and it does something genuinely useful: a real shell environment in your pocket without a server. ShellDrop is the inverse: it does nothing locally, exists only to talk to a remote machine over SSH, and is tuned for managing AI coding agents in tmux on that remote machine.
The two apps don't really compete. They share a category and aim at orthogonal use cases. Still, the comparison comes up. Here it is.
| ShellDrop | a-Shell | |
|---|---|---|
| Is this iOS terminal app a piece of art? | yes | no |
| Pricing model | Free. No in-app purchases. | Free, open-source |
| Primary purpose | Remote SSH client | On-device Unix shell |
| Platforms | iPhone, iPad (iOS 17+) | iPhone, iPad, Apple Silicon Mac |
| Account required | No | No |
| Telemetry | None | None |
| SSH client | First-class, with manager + keys | ssh binary available at the prompt |
| Local Unix tools (vim, grep, python) | No | Yes |
| Public-key auth (SSH keys) | Yes (v4.1.0+, Secure Enclave P-256) | Yes, via ssh-keygen at the prompt |
| tmux single-finger scroll | Yes | Standard scroll |
| iPad layout (incl. 13" iPad Pro M4) | Universal app, full-canvas landscape, centred toolbar | Universal app, iPad supported |
| Custom command shortcut | One Tap toolbar button (v3.1.4+) | Shell aliases |
| Open source | No | Yes (GitHub) |
ShellDrop is built with the design as a feature. The hero is a live cyan mesh that breathes behind the brand, six droplet nodes drifting on the edges with master-shot lines tracing connections between them. Switching from Home to a session triggers a per-element shrink cascade where the layout itself animates. The droplet metaphor carries from the App Store icon through tabs and sessions. Built natively in SwiftUI for iOS 17+.
ShellDrop is built around the SSH connection manager. Save hosts, keys, sync via iCloud CloudKit, hop between sessions in tabs. a-Shell has an ssh binary you can run from its prompt; the workflow stays at the shell level rather than the app level.
Single-finger swipe through tmux scrollback without entering copy mode. The toolbar carries Esc, Ctrl-C, arrow keys, Shift-Tab, and a tmux detach button at all times. If most of your remote work is inside a tmux pane attached to a coding agent, that is the difference.
v4.1.0 generates P-256 keys inside the iPhone Secure Enclave. Private key cannot be exported, even by the app. a-Shell uses standard software ssh-keygen.
Universal app, full landscape, hardware-keyboard friendly. Toolbar centres on the big canvas.
This is the whole point of a-Shell. You can write code, run Python or Lua scripts, edit files in vim, use git, all on the device, without an SSH session. If you want to learn Unix tooling, prototype quickly without a server, or have a usable shell when you're offline, a-Shell is built for that. ShellDrop has none of this.
a-Shell is open-source on GitHub. ShellDrop is closed-source.
a-Shell has done interesting work integrating Python, Lua, JS, and WebAssembly tooling into the on-device sandbox. There is a genuine little Unix world inside it.
a-Shell runs on Apple Silicon Macs via the iPad-on-Mac path. ShellDrop is iOS / iPadOS only.
Running both is the right answer for many people. a-Shell when you're offline or learning, ShellDrop when you're SSH-ing into your real machine.
Yes. Open-source and free on the App Store. ShellDrop is also free.
a-Shell is an on-device Unix shell that includes an ssh binary. ShellDrop is a dedicated SSH client app with a connection manager, key store, tmux scrollback, and One Tap.
Yes. a-Shell ships a sandboxed Python and many Unix tools. ShellDrop does nothing locally; it only connects out over SSH.
Yes from v4.1.0. Ed25519, ECDSA P-256/P-384/P-521 paste-import, plus Secure Enclave-backed P-256 keys.
ShellDrop. The whole app is built around remote tmux sessions attached to coding agents. a-Shell can SSH but is not optimised for that workflow.
ShellDrop is on the App Store. Universal iPhone and iPad, iOS 17+. Free, no subscription.
