Encryption
How PinkyBond encrypts messages and calls
Everything she shares with you is encrypted on her phone and decrypted on yours. Our server forwards sealed envelopes it cannot open. We never hold the key.
Built on platform cryptography
We did not write our own crypto. On iPhone we use Apple's CryptoKit. On Android we use Google's Tink. Curve25519 key agreement, HKDF-SHA256 and AES-256-GCM on both, pinned to each other by shared test vectors, so an iPhone and an Android phone produce byte-for-byte identical ciphertext.
Key agreement
Curve25519 (X25519) ECDH
Encryption
AES-256-GCM
Key derivation
HKDF-SHA256
What we do, and what we don't
Every row is checkable. The last three are where we fall short of the best messengers, and we would rather you read that here than find it out later.
| Dimension | PinkyBond |
|---|---|
| Encryption | AES-256-GCM, end-to-end between the two phones |
| Key agreement | Curve25519 (X25519) ECDH, then HKDF-SHA256 |
| Implementation | Apple CryptoKit on iPhone, Google Tink on Android — byte-for-byte interoperable |
| Key storage | iOS Keychain / Android Keystore, hardware-backed where available |
| Pairing | QR code in person, or a 6-character code / link exchanged remotely; both public keys exchanged |
| Verification | A 6-digit code on both phones confirms no one sat in the middle |
| Account | None — no phone number, no email, no password |
| Akses pelayan kepada kandungan mesej dan panggilan | Tiada. Kami tidak pernah memegang kunci itu. |
| What the relay stores | ID penggandingan, jenis mesej, cap masa, saiz, teks disulitkan — dipadam sebaik sahaja dihantar, paling lama 30 hari |
| Foto, video dan fail | Sehingga 2 GB, dimeteraikan dengan kunci baharu bagi setiap fail yang hanya dimiliki oleh kedua-dua telefon anda; dipadam sebaik sahaja dimuat turun, paling lama 30 hari. Kepada aplikasi pasangan yang belum dikemas kini: sehingga 25 MB di bawah kunci penggandingan, disimpan selama 30 hari |
| Log panggilan | Telefon mana yang membuat panggilan, bila, suara atau video, hasilnya dan tempoh — boleh dibaca oleh pelayan kami, disimpan selama 90 hari, dipadam apabila anda nyahgandingkan. Tidak pernah audio atau video. |
| Push notifications | Carry no text; the phone decrypts locally |
| Safety Mode | Yes — her phone sends neutral substitute data instead of her real status. Your app shows no indicator, though the flag itself is in the snapshot. |
| Forward secrecy | No — one key per pairing |
| Open source | No |
| Independent audit | Not yet |
How pairing works
No phone number. No email. No account. In the same room, she shows a QR code and you scan it. Apart, she sends you a 6-character code or a link. Either way both phones exchange public keys, derive the same secret, and show a 6-digit verification code so the two of you can confirm no one sat in the middle.
She taps “Pair with partner” in PinkyBloom
Her phone generates a Curve25519 key pair (Apple CryptoKit on iPhone, Google Tink on Android)
She shows a QR code, or sends you a 6-character code or link if you are apart
You scan or enter it in PinkyBond, and your phone generates its own key pair
Your public key travels back to her the same way; both phones now hold both public keys
Each phone runs ECDH and HKDF-SHA256 to derive the same shared secret — nothing secret crosses the network
The shared secret is stored in the iOS Keychain or the Android Keystore
A 6-digit verification code appears on both phones; if they match, no one sat in the middle
The Blind Relay
Pelayan kami ialah peti mel untuk sampul yang dimeteraikan. Ia hanya menyimpan teks disulitkan sehingga telefon yang satu lagi mengambilnya, kemudian memadamnya — paling lama selepas 30 hari, jika telefon itu kekal luar talian. Ia tidak pernah menyimpan kunci. Notifikasi tolak tidak membawa sebarang teks; telefon menyahsulit secara setempat.
PinkyBloom
Encrypts on her phone
Blind Relay
Menyimpan teks disulitkan sehingga dihantar, paling lama 30 hari
Cannot decrypt
PinkyBond
Decrypts on your phone
Segala yang pelayan kami simpan tentang satu mesej, satu fail dan satu panggilan:
pairingId
Identifier for the pairing; not a name, number or email
senderRole
Which app sent it: PinkyBloom or PinkyBond
messageType
Jenis sampul apakah ia — contohnya mesej sembang, tangkapan status, resit atau persediaan panggilan — tidak pernah apa yang ada di dalamnya
timestamp
When it was sent
ciphertext
AES-256-GCM blob we cannot open; its length is the only thing we can measure
retention
Dipadam sebaik sahaja telefon yang satu lagi menerimanya; paling lama 30 hari jika ia kekal luar talian
relayReceipts
Selepas penghantaran, satu rekod tanpa kandungan: mesej yang mana dan sama ada ia dihantar atau tamat tempoh. Disimpan 30 hari, supaya telefon penghantar dapat memaparkan “tidak dihantar”
mediaObjects
Foto, nota suara, video dan fail sehingga 2 GB, disimpan sebagai teks disulitkan di Cloudflare R2 dengan kunci baharu bagi setiap fail yang hanya bergerak di dalam mesej tersulit. Dipadam sebaik sahaja telefon pasangan anda memuat turunnya; paling lama 30 hari
callLog
Telefon yang mana antara kedua-dua telefon membuat panggilan, bila, suara atau video, dijawab, tidak dijawab atau ditolak, dan berapa lama tempohnya. Boleh dibaca oleh pelayan kami — begitulah caranya telefon yang mati masih tahu tentang panggilan tidak dijawab. Disimpan 90 hari, dipadam apabila anda nyahgandingkan. Tidak pernah audio atau video
Calls
Voice and video are peer-to-peer WebRTC with DTLS-SRTP and fresh keys for every call. The call setup rides the encrypted relay like any message. Before media flows, your phone checks the peer's DTLS fingerprint against a key derived from the pairing secret; a failed check aborts the call.
Apabila rangkaian menyekat laluan terus, geganti menghantar paket yang tidak dapat dibacanya. Tiada pelayan media pernah mendengar panggilan, dan tiada panggilan dirakam. Ia berfungsi antara iPhone dan Android. Apa yang pelayan kami simpan ialah log panggilan — telefon mana yang membuat panggilan, bila, suara atau video, hasilnya dan berapa lama tempohnya — selama 90 hari, supaya pasangan yang telefonnya mati tetap nampak panggilan tidak dijawab. Lebih lanjut di /calls.
Safety Mode
Encryption protects her data from outsiders and from us. Safety Mode is for the case where the person on the other end is the concern. She can pause sharing at any time, and he is never notified. She can also turn on Safety Mode, which substitutes neutral data he cannot distinguish from a real update.
When Safety Mode is active, the partner sees:
Phase
“Follicular”
Mood
“Good”
Energy
3 (Moderate)
The neutral data is encrypted and sent through the normal relay, so it looks the same as a real update in transit and on his screen.
Questions
Encrypted between the two phones. We never hold the key.
No phone number, no email, no account. The same cryptography on iPhone and Android, and a relay that forwards ciphertext it cannot open.
