安装包图标

Kryptos

Encrypt inside any messenger: the keyboard encrypts, the screen decrypts
新版本 2.3.2
Chinese: interface and a keyboard layout with pinyin input.
Rude and unsafe words are out of the text steganography dictionaries, still 4096 words per language. Covers made by the word and sentence modes cannot be read by versions before 2.3.2, both sides have to update.
Keyboard: bigger buttons, adjustable field size, the badge can be hidden.
Send after encrypting now works in messengers with their own send button.
Profiles and contacts can be renamed.
Around twenty fixes.
Kryptos encrypts right inside the conversation, so you never have to run between apps.

The Kryptos keyboard installs like any other system keyboard: turn it on once and it is there everywhere you type. Write your message in WhatsApp, Telegram or an SMS, tap the padlock, and what is left in the field is the ciphertext, ready to send. Incoming messages Kryptos decrypts by itself, right over the chat as you scroll it, with nothing to copy and nowhere to switch. Both the keyboard and the on-screen decryption are built into the system, so they work in any app.

It is the same app on iPhone and on Android and the two are fully compatible. It does not matter which phone your contact has.

The encryption is the real thing: the Signal Protocol through Signal's own libsignal library, a fresh key for every message and protection even against future quantum computers. A contact can be verified by safety number. When a full chat is more than you need, there is a simple mode built on one shared password, and for those who live on PGP that is built in too. All the messenger ever sees is a meaningless run of characters, with no recognizable markers.

Steganography hides the very fact that you are writing: the ciphertext can be buried inside an ordinary photo or disguised as a harmless run of real words. Without the password there is nothing in the photo to test for.

Nothing goes online: there is no networking code in the app at all, and the build ships without the INTERNET permission. It asks only for the camera to scan QR codes, vibration and overlay control. No accounts, no phone number, no servers, no analytics. Keys are created on the phone itself, kept in the Android Keystore and never leave it.

Entry can be closed off with biometrics or a passcode. There is also a panic password: typed into the same field, it wipes everything for good instead of unlocking. The clipboard clears itself, messages can disappear on a timer, screenshots and the app-switcher snapshot can be blocked, and all your keys can be exported into one password protected file to move them to a new phone.

Also inside: light and dark themes, an app language separate from the system one, a step-by-step guide with answers to common questions, and a keyboard with suggestions, autocorrection and emoji for English, Russian and German, entirely offline.

版本

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  • 版本 2.3.2 (10) 推荐 更新于 2026-08-21

    arm64-v8a armeabi-v7a

    该版本需要 Android 8.0 及以上版本。

    此包由原始开发者构建并签名,并保证对应于此源代码 tarball

    权限
    • 拍摄照片和视频
      当你使用此应用时,它可以使用相机拍摄照片和录制视频。
    • 隐藏来自其他应用的叠加内容
      此应用可请求系统隐藏来自其他应用的叠加内容,以免这些内容显示在此应用之上。
    • 使用生物特征硬件
      允许此应用使用生物识别硬件进行身份验证
    • 使用指纹硬件
      允许此应用使用指纹硬件进行身份验证
    • 控制振动
      允许此应用控制振动器。
    • com.kryptos.android.DYNAMIC_RECEIVER_NOT_EXPORTED_PERMISSION

    下载 APK 22 MiB PGP 签名 | 构建日志

  • 新版本 2.3.1
    New
    - Full German: interface, QWERTZ layout with its own dictionaries, steganography.
    - Length masking now covers steganography too.
    - Android: the lock key can send the message right away.

    Fixed
    - On-screen stego decryption broke on names and stray words.
    - The key preview showed in screen recordings inside password fields.
    - Stalls on launch, on long clipboard text and in PGP are gone.

    The stego format changed: older builds will not open length-masked messages.
  • 版本 2.3.1 (9) - 更新于 2026-08-11

    arm64-v8a armeabi-v7a

    该版本需要 Android 8.0 及以上版本。

    此包由原始开发者构建并签名,并保证对应于此源代码 tarball

    权限
    • 拍摄照片和视频
      当你使用此应用时,它可以使用相机拍摄照片和录制视频。
    • 隐藏来自其他应用的叠加内容
      此应用可请求系统隐藏来自其他应用的叠加内容,以免这些内容显示在此应用之上。
    • 使用生物特征硬件
      允许此应用使用生物识别硬件进行身份验证
    • 使用指纹硬件
      允许此应用使用指纹硬件进行身份验证
    • 控制振动
      允许此应用控制振动器。
    • com.kryptos.android.DYNAMIC_RECEIVER_NOT_EXPORTED_PERMISSION

    下载 APK 21 MiB PGP 签名 | 构建日志

  • 新版本 2.3
    Kryptos 2.3

    * Panic password: a second password that wipes everything instead of unlocking.
    * App passcode, for unlocking without biometrics.
    * Key backup: your keys, contact keys and PGP keys in one password protected file.
    * Argon2id everywhere, PBKDF2 removed.
    * Photo steganography rebuilt: no visible signature, keyed adaptive placement.
    * On-screen decryption finds messages in real messengers again.
    * Password protected messages and stego photos from older versions no longer open.
  • 版本 2.3 (8) - 更新于 2026-08-05

    arm64-v8a armeabi-v7a

    该版本需要 Android 8.0 及以上版本。

    此包由原始开发者构建并签名,并保证对应于此源代码 tarball

    权限
    • 拍摄照片和视频
      当你使用此应用时,它可以使用相机拍摄照片和录制视频。
    • 隐藏来自其他应用的叠加内容
      此应用可请求系统隐藏来自其他应用的叠加内容,以免这些内容显示在此应用之上。
    • 使用生物特征硬件
      允许此应用使用生物识别硬件进行身份验证
    • 使用指纹硬件
      允许此应用使用指纹硬件进行身份验证
    • 控制振动
      允许此应用控制振动器。
    • com.kryptos.android.DYNAMIC_RECEIVER_NOT_EXPORTED_PERMISSION

    下载 APK 20 MiB PGP 签名 | 构建日志