Osmium

Osmium

Privacy-first offline TOTP/HOTP authenticator

Hongxi Li Password & 2FA Security

Download (5.0 MB) Website

Screenshots

Screenshot of Osmium Screenshot of Osmium Screenshot of Osmium

Description

Osmium is a privacy-first, fully offline authenticator for two-factor codes (TOTP/HOTP): codes are generated on-device and work without any network connection.

• Codes are computed entirely on-device — no account, no sign-up, and no telemetry.
• No connections at start-up. Osmium goes online only when you ask it to: the automatic update check is off by default, and the Terms of Use / Privacy Policy are downloaded from osmium.im only when you open them.
• Secrets are encrypted with a non-exportable key in the Android Keystore before they are written to disk.
• TOTP and HOTP: 6/7/8 digits, SHA-1/SHA-256/SHA-512; Steam Guard codes supported.
• Organize accounts with tags and search.
• Import from other apps: Google Authenticator (QR migration), Aegis, 2FAS and other common backup formats.
• Encrypted export & restore to a local file or your own WebDAV server; encrypted quick transfer between two devices on the same Wi-Fi.
• Modern Material 3 design with light/dark themes and Material You colours.
• Fully open source (GPL-3.0-or-later); release builds are reproducible — anyone can verify that the published APK matches the source code.

No ads, no trackers, no analytics.

Website: https://osmium.im
Source code: https://github.com/lihongxi-g/osmium-authenticator

Versions

Version Date Size Requires Android Download
2.6.0 current
66b0c47e95ea8804…
 2026-10-27 5.0 MB API 26
2.6.0
e7408334ce2dcfa8…
 2026-10-27 4.9 MB API 26
2.6.0
bdfe429676f948ba…
 2026-10-27 4.9 MB API 26

Permissions

What the app asks the system for. Android only grants sensitive access after you confirm it.

  • CameraTake photos and videos.
  • BiometricsUnlock with fingerprint or face.
  • VibrationControl the vibration alert.
  • Internet accessSend and receive data over the internet.
  • Network stateCheck whether and how the device is connected.
  • Wi-Fi stateRead information about the Wi-Fi connection.
  • CHANGE_WIFI_MULTICAST_STATE
  • Write storageCreate and change files on the device storage.
Show 9 more permissions
  • NotificationsShow notifications.
  • Run at startupStart automatically after the device is switched on.
  • REQUEST_IGNORE_BATTERY_OPTIMIZATIONS
  • ACCESS_LOCAL_NETWORK
  • FingerprintUnlock with a fingerprint.
  • Prevent sleepingKeep the device from going to sleep.
  • Foreground serviceKeep running in the background, visible in the status bar.
  • authenticator.DYNAMIC_RECEIVER_NOT_EXPORTED_PERMISSION
  • Read storageRead files on the device storage.

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