Terminal Spike: a Native Android Terminal

Terminal Spike is my native Android terminal app for working on remote machines from a phone. It brings SSH connections, multiple terminal tabs, tmux sessions, and file transfers into a workspace that keeps its settings and connection details on the device.

A short demo

This recording shows me using a remote coding session, entering prompts, scrolling through terminal output, and switching between tmux sessions. The extra-key bar keeps terminal controls close to the phone keyboard.

The coding tool runs on the connected machine. Terminal Spike provides the terminal and input controls; it does not bundle an AI model or require an AI subscription of its own.

Remote work from a phone

The app supports password and private-key SSH authentication, saved connections, and several simultaneous terminal tabs. It verifies server host keys and warns when a known server’s key changes.

Alongside the terminal, there is an SFTP file manager for browsing, uploading, downloading, renaming, and deleting remote files. Saved command snippets and a configurable extra-key bar make frequently used commands and keys such as Ctrl, Esc, and the arrows easier to reach. Fonts, colours, text size, and cursor behaviour are configurable too.

One useful part of the remote coding workflow is image input. Terminal Spike can transfer a clipboard image over an authenticated SSH connection to a private cache directory on the connected host, then paste its remote path into the terminal. That lets a remote tool work with an image from the phone.

Building the terminal

The app uses Kotlin and Jetpack Compose for its application UI. The terminal itself is a custom Android View that draws rows directly with Canvas and Paint. That separates the terminal’s rendering and screen state from the surrounding connection lists, settings, and session controls.

The terminal engine handles primary and alternate screens, cursor movement, scroll regions, colours, bracketed paste, and common terminal queries. Scrollback is bounded. For app-selected tmux sessions, a separate local history model supports scrolling on the phone, while an explicit remote-mouse mode is available for interacting with terminal applications that use it.

Mosh support is implemented through an optional, separately installed extension. SSH works without it. Keeping the transport extension separate also keeps its native dependencies and lifecycle outside the main app.

Keeping data on the device

Terminal Spike has no app account, analytics, advertising, or cloud-sync service. Connections go directly to the hosts the user chooses. Imported private keys and passwords that the user explicitly chooses to save are encrypted using an app-specific Android Keystore key.

The privacy policy explains credential storage, remote connections, permissions, and backups in more detail.

See Terminal Spike on the Projects page for the app overview and demo.