Termphin

Termphin is an SSH client that keeps the shell alive on the server so that sessions survive locked screens, lost signals, and network switches. It is a mobile terminal built for developers, system administrators, and anyone who manages remote machines from a phone, and it combines a fast terminal with an integrated SFTP browser and editor, a snippet runner, an SSH key manager, port forwarding, ProxyJump bastion chains, and a biometric lock. The stated purpose is simple and repeated throughout the site: never lose an SSH session again. Your shell stays alive on the server through locked screens and network drops, and when you come back you are put on the same screen you left. Termphin is available on Google Play, is free to use, and comes with no ads and no in-app purchases. The site also positions it explicitly as built for productivity and built for AI coding agents such as Claude Code and OpenCode. The problem Termphin targets is specific and well documented. A blog post on the site asks why your SSH session dies when you lock the screen, and answers with the mechanics of mobile app suspension: mobile SSH connections drop when an app is suspended, and the post covers what the client does to stay scheduled and how a remote helper keeps long-running shells alive. On a phone, locking the screen, losing a signal, or switching from Wi-Fi to mobile data has traditionally terminated the connection, and with it any job that was running. That matters most for work that takes minutes rather than seconds - deploy scripts, database migrations, builds, or AI coding agent tasks - where a dropped session can mean losing both the process and the context of what it was doing. Termphin's answer is to move the shell off the app and onto the server. Persistent sessions are the core of the product. Termphin maintains the connection while the app is backgrounded or the phone is locked, and it relies on the Termphin Agent: a tiny, open-source helper that holds the remote shell open and reattaches instantly when you return. Because the shell runs on the server rather than inside the app, your jobs keep running even if you lock your phone or lose signal. The FAQ explains that if the connection drops or you switch networks, the small open-source Rust agent on the server keeps the remote shell running and reattaches you seamlessly upon reconnect. For basic sessions no helper is required at all, since shell detection is automatic, which means the agent is an enhancement for persistence rather than a prerequisite for connecting. Terminal rendering gets its own emphasis. Termphin draws the TUI directly with Flutter rather than inside a web view, which the site says keeps htop, vim, and other terminal user interfaces rendering without broken box characters. The pixel-perfect TUI section adds that spinners, progress bars, and diff views render cleanly without mangled characters - a practical difference when you are reading a diff or watching a progress bar on a small screen. Appearance is configurable as well, with 14 color schemes and controls for font size, line height, and padding, all previewed live in the terminal before you commit to a setting. The toolbox covers the day-to-day tasks around a remote shell. SSH tunnels let you open local and remote port forwards per session, or save them with a profile so they come back with the connection. Integrated SFTP puts a full file browser a tab away from the terminal: you can browse remote files, edit them with syntax highlighting, preview images remotely, and resume file transfers that were interrupted. A one-tap SFTP upload flow lets you upload files from your phone and then paste their remote server path straight into your prompt, which removes the usual guesswork about where an upload landed. Machines, snippets, and key management round out the toolset. In the machines list you save the host, user, and credentials once, then tag, search, and connect in one tap; the site lists fast search and tags, ProxyJump bastion chains, and multi-tab concurrent sessions as the organizing features. Snippets let you save recurring commands once and trigger them instantly across your infrastructure, with a search-and-run palette, execution history that records exit codes, and a customizable action dock. Security is handled by a device-bound key vault: keys and profiles are sealed with AES-256-GCM behind your phone's PIN or fingerprint, you can generate ed25519 and RSA keys, biometric PIN and fingerprint lock gate access, and host key pinning happens on connect. The unique approach is the split between client and server. Instead of holding the shell inside a mobile app that the operating system can suspend, Termphin keeps the shell running remotely and treats the app as a window onto it, reattaching when you return. Termphin says it maintains the connection while backgrounded or locked, and connections go directly to your server with host key verification rather than through an intermediary. Data protection stays local: keys and profiles are sealed in an AES-256-GCM vault on the phone, gated by PIN or biometrics, and only opt-in anonymous crash analytics are ever sent. Two of the pieces are open source on GitHub - the terminal renderer, terminal_view, and the server helper, termphin-agent - so the persistence mechanism can be inspected rather than taken on trust. The benefits follow from that architecture. Long jobs keep running when the phone is locked or the signal drops, and you reattach anytime rather than restarting. Terminal output stays legible because the TUI is drawn natively, so htop, vim, spinners, progress bars, and diffs do not degrade into mangled characters. Credentials and keys stay on the device in an encrypted vault rather than being typed repeatedly, and profiles, tags, and search turn a list of servers into something you can navigate in a tap. Snippets cut repeated typing down to a single action, and because the session survives network changes, switching between Wi-Fi and mobile data stops being a destructive event. Concrete scenarios are described on the site. The AI coding agents section gives the clearest one: start a ten-minute Claude Code or OpenCode task and pocket your phone, because the agent runs on your server and the session never aborts. The FAQ confirms that Claude Code, Codex, and OpenCode run seamlessly, that tasks keep executing when the screen locks, and that TUI diffs and progress bars render cleanly. Other workflows in the content include reaching a server behind a bastion by pointing a profile at a jump host, running interactive keyboard prompts for 2FA authenticator codes (TOTP) and PAM passwords, browsing and editing a remote file over SFTP without leaving the app, and triggering saved recurring commands across infrastructure from a search-and-run palette. Termphin is aimed at people who work on remote servers from a phone: developers, administrators, and anyone running long-lived processes or AI coding agents over SSH. It works with any server reachable over standard SSH - Linux, macOS, BSD, or Windows - with automatic shell detection, and it interoperates with bastion setups through ProxyJump-style jump hosts and with 2FA through TOTP and PAM prompts. The stack described on the site includes Flutter for the terminal rendering, a Rust server agent, and AES-256-GCM for the local vault. Pricing is straightforward: Termphin is free to use with no ads and no in-app purchases, distributed through Google Play. In short, Termphin's value proposition is that the shell lives on the server while you live on your phone. By keeping sessions alive through locked screens, lost signals, and network switches, rendering terminal interfaces properly, and bundling SFTP, tunnels, snippets, key management, and bastion support into one free Android app, it turns mobile SSH from a fragile short-lived connection into something that behaves like a persistent workstation.