FreeFTP connects your phone to your own servers over FTP, FTPS and SFTP. It is
free in both senses: no advertising, no paid tier, no analytics, and no account.

The app talks to your servers and to nothing else. It holds one network
permission, and the only host it ever contacts is the one you typed in.

Features

* FTP, FTPS (explicit and implicit) and SFTP in a single client.
* Browse, download, upload, rename, delete and create folders.
* Read files without downloading them. Tap any text file and it is streamed
straight into memory, with nothing written to your storage. The encoding is
detected and shown, so you can tell real content from mojibake.
* Download whole folders, recursively, with their structure preserved.
* Multi-select: long-press to start, then download or delete in bulk. Large jobs
ask for confirmation first, and deleting always asks.
* A transfer queue with live progress, pause, resume, cancel and retry. A paused
transfer keeps what it has and continues from that point.
* Downloads land in your Downloads folder, where you can actually find them, or
in any folder you choose. No storage permission is requested: you grant access
to the one folder you pick.

Security

* SSH host keys are checked. An unrecognised server is refused until you have
seen its SHA-256 fingerprint and accepted it, and a key that later changes is
refused outright.
* TLS certificates are verified for FTPS, with an explicit opt-in for
self-signed ones.
* Passwords, key passphrases and private keys are encrypted at rest with a key
held in the Android key store.
* Password, SSH key (with passphrase) and anonymous authentication, falling back
automatically across publickey, password and keyboard-interactive.

FreeFTP handles the awkward parts of real-world FTP: passive and active mode,
MLSD with a LIST fallback, a dozen server listing dialects, UTF-8 negotiation,
and resuming an interrupted transfer.