Termphin

Termphin is an SSH client for phones whose central promise is simple: never lose an SSH session again. Your shell stays alive on the server through locked screens and network drops, so instead of watching a connection die you reconnect and pick up right where you left off. Around that idea it bundles a full remote-work toolbox — an integrated SFTP client with a syntax-highlighted editor and remote image previews, an SSH key manager, a snippet runner, port forwarding, ProxyJump bastion chains and multi-tab sessions — plus a terminal renderer that draws htop, vim and other full-screen programs cleanly. It is built for people who manage remote servers from a phone, including those who run long AI coding agents such as Claude Code, Codex and OpenCode, and it is free with no ads and no in-app purchases. The problem Termphin addresses is structural to mobile SSH. When an app is suspended — the screen locks, the phone goes in a pocket, signal is lost, or you switch from Wi-Fi to mobile data — the connection drops, and with it the remote shell and anything running inside it. A deploy three quarters of the way through, a database migration, a build, a long-running task started by an AI coding agent: all of it dies with the socket. Because most clients run the terminal entirely inside the app, being scheduled out of the foreground is enough to kill the session. On top of that, full-screen terminal programs frequently render badly on mobile clients, showing broken box characters, mangled spinners and unreadable diff views, which makes tools like htop and vim impractical to use. Termphin attacks both problems at once: the shell lives on the server rather than in the app, and the renderer is written to draw terminal output properly. The core mechanism is a lightweight server helper. Termphin describes a tiny open-source Rust agent that runs on the server and holds the remote shell open. The shell runs on the server, not in the app — that is the phrasing the site uses to describe the approach — so even if you lock your phone or lose signal, your jobs keep running. When you come back, the agent reattaches you to the same screen instead of leaving you at a fresh prompt. Termphin also maintains the connection while the app is backgrounded or locked, and if the connection does drop or you switch networks, the agent keeps the remote shell alive and reattaches you seamlessly on reconnect. For basic sessions, shell detection is automatic and no helper is required. Rendering is handled directly by Flutter rather than in a web view, which the site presents as the reason htop, vim and other TUIs render without broken box characters. Spinners, progress bars and diff views render cleanly without mangled characters — the detail that makes AI agent output readable on a small screen. Appearance is configurable too: Termphin ships with 14 color schemes and lets you fine-tune font size, line height and padding against a live terminal preview, so you can size text comfortably for a phone screen without guessing. The toolbox covers the everyday work around a shell. Integrated SFTP puts a complete file client beside the terminal: browse remote files, edit them in a syntax-highlighted editor, preview images one tab away, and transfer files with resumable transfers. One-tap SFTP upload lets you upload a file from your phone and paste its remote server path straight into your prompt. Snippets let you save recurring commands once and trigger them instantly across your infrastructure, through a search-and-run palette, execution history with exit codes, and a customizable action dock. Machines are organized by saving host, user and credentials once, then tagging, searching and connecting in one tap, with fast search and tags, ProxyJump bastion chains and multi-tab concurrent sessions. SSH tunnels let you open local and remote port forwards per session or save them with profiles. Security is built around a device-bound key vault. SSH keys and profiles are sealed with AES-256-GCM on your phone and protected behind your phone's PIN or fingerprint. You can generate ed25519 and RSA keys, lock the app with biometric PIN and fingerprint, and use host key pinning on connect. Connections go directly to your server with host key verification, and the only data ever sent is opt-in anonymous crash analytics. Interactive keyboard prompts for two-factor authentication codes (TOTP) and PAM passwords are fully supported. Overall the product works as a split between phone and server. The client handles presentation, configuration and local secrets; the server-side agent handles continuity. That division is what makes reattachment possible: when the app is suspended the remote shell simply keeps running under the agent, and returning to the app is a reattach rather than a new login. The benefits follow from that design. Long jobs finish even when the phone is locked, so you can start something and pocket the phone instead of babysitting a progress bar. Sessions resume on the same screen, which preserves scrollback, running processes and the state of an interactive program. Clean TUI rendering means command-line tools that assume a real terminal are actually usable from a phone. And because keys and profiles live in an encrypted, biometric-gated vault on the device, that convenience does not come at the cost of exposing credentials. It is free — no ads, no in-app purchases. Concrete scenarios the content describes include starting a 10-minute Claude Code or OpenCode task and pocketing your phone while the agent runs on your server and the session never aborts; running deploys, image builds, registry pushes and database migrations where the output stream matters and the process must not be interrupted; reaching a server behind a bastion by pointing a profile at a jump host so traffic remains encrypted end-to-end between the phone and the target server; uploading a file from the phone over SFTP and pasting its remote path into a prompt; running saved snippets across infrastructure from a search-and-run palette; and using full-screen tools like htop and vim on a phone with correct character rendering. Termphin runs on Android and is available on Google Play. The download section states that Termphin is free to use, with no ads and no in-app purchases. It works with any server reachable over standard SSH — Linux, macOS, BSD and Windows — with automatic shell detection. Both the terminal renderer (terminal_view) and the server helper (termphin-agent) are open source on GitHub, and an engineering blog documents how it is built and why, covering topics such as SFTP throughput and why SSH sessions die when the screen locks. The takeaway is that Termphin reframes mobile SSH around continuity rather than connectivity: the shell belongs on the server, the phone is just a window onto it, and a small open-source agent keeps that window's contents alive. Combined with a proper TUI renderer, an SFTP client, snippets, tunnels and a device-bound key vault, it turns a phone into something you can genuinely run long remote work from — and it does so for free.