DotBGE is the official app for the open .bge encryption format. It lets you lock a file to a specific person, or to a password — entirely on your device.
Encryption, without the ceremony
Strong file encryption usually means command lines, key servers, or trusting a company with your data. DotBGE removes the ceremony. You pick a file, choose who (or what password) should be able to open it, and you get a single .bge file you can send anywhere. Decrypting is just as direct: open the file, authenticate, done.
There are no accounts and no DotBGE servers. Everything happens locally, using standard cryptography — RSA-4096 for identities and AES-256-GCM for the file contents.
The app and the format
It helps to separate two things:
- .bge is the format — an open, documented container for encrypted files. Anyone can read the specification and build a tool that reads or writes it. The full spec lives at dotbge.com.
- DotBGE is the app — a native implementation of that format for iPhone, iPad, and Mac, with an interface designed so anyone can use it.
Because the format is open, your files aren't trapped in one vendor's product. That's the point: encryption you can verify, in a format that outlives any single app.
Two ways to lock a file
Identity mode
Encrypt a file to a person's identity. Only the holder of that identity's private key can open it — not even you can, unless it's also yours. You exchange identities by sharing an identity card (a QR code or a small file), and store contacts' public keys to encrypt for them later.
Password mode
Encrypt a file with a passphrase. Anyone who knows the password can open it — useful when you can't exchange keys ahead of time. The key is derived from your passphrase with PBKDF2; the password is never stored.
Your keys stay yours
Your private key is generated on-device and kept in the system Keychain, protected by Face ID, Touch ID, or your passcode. It is never uploaded to us. If you choose, your own iCloud can sync it across your Apple devices — but it never passes through DotBGE.
Everywhere you work
DotBGE runs on iPhone and iPad, with a Mac app and command-line tool for desktop workflows. On iOS you can encrypt straight from the Share sheet in any app, and keep encrypted files in a biometric-locked vault that can sync through your private iCloud.
Read the format
If you want the technical details — the byte layout, the algorithms, and how to build your own reader — that's all documented openly.