Pick the recipient.
Open the conversation with the person the file is for. Files are always sent to a specific paired contact — that's whose key seals it.
// guide / send-an-encrypted-file
How to send an encrypted file.
Files travel with the same guarantees as messages: encrypted to your contact, signed by you, opaque to the relay. Anything up to 50 MB, with a dedicated Files tab so transfers never get lost in the scroll.
// at a glance
- Open the conversation
- Attach a file or photo
- Send — it's sealed automatically
- Find it later in the Files tab
Prerequisites
- A paired contact
Attach the file.
Attach a photo from your library or a document from the file picker. Anything up to 50 MB per file works.
Send it.
That's the whole job. CarrierPony encrypts the file to your contact's key, signs it with yours, and hands the sealed envelope to the relay for delivery.
Find it again in Files.
Every sent and received file also appears in the dedicated Files tab, so transfers have one home on both ends.
Verify it worked.
- The file shows as delivered in the conversation.
- Your contact opens it and the signature verifies.
- The transfer is listed in the Files tab.
Common questions.
What happens with files over 50 MB?
The app will tell you rather than silently failing. For bigger payloads, compress first or split the content.
Does the relay store my files?
Only as a sealed envelope in transit, deleted on delivery — the same lifecycle as any message. It can't open them.
Are files re-compressed or touched?
Your contact receives exactly the bytes you sent — the signature verifies that. Nothing in the path can modify the file without detection.
Next steps.
Get CarrierPony
Free private messaging and file transfer for iPhone. Currently in App Review — leave your address for exactly one email on launch day.