Encrypted.
Where it counts.

Your data. Your gains. No exceptions.

Most fitness apps store your personal data in plaintext on their servers. reppd can encrypt your personal profile data and body measurements on your device before they reach us — on the server they are then just encrypted blobs we cannot read. To be clear: your workouts, sets and plans are not end-to-end encrypted. They are stored in our database in Frankfurt, protected by transport and at-rest encryption and access rules, so that sync, statistics and Spotter can work.

On your device
Height: 184 cm
Weight: 88 kg
DOB: 12.03.1994
AES-256
On our servers
xK9f2mQz8vLp4nRw
A7cJ3hT6yB1dU5sE
qW0gV8kM2xZ4oP9i

See it in action.

Type something personal — watch it become unreadable.

Your Device
Our Servers Encrypted
This is what our servers see. Meaningless without your key.

What we encrypt

Once you enable encryption, these personal fields are encrypted on your device. Our servers only store them as encrypted blobs — opaque data we cannot read. Without encryption, they stay on your device and are not synced. Workouts, sets, plans and statistics are not end-to-end encrypted.

Personal Profile

  • Name
  • Date of birth
  • Gender
  • Height
  • Body weight

Body Measurements

  • Weight
  • Chest
  • Waist
  • Hip
  • Biceps
  • Thigh
  • Calf
  • Notes

Key architecture

When you enable encryption, your app generates a random 256-bit Data Encryption Key (DEK). It encrypts your data with AES-256-GCM and is kept in your iCloud Keychain so your devices know it. You also get a recovery key: it wraps the DEK (via HKDF-SHA256 and AES-256-GCM), and only this wrapped version is stored on our server — never the plaintext key, never the recovery key. You can generate a new recovery key without re-encrypting your data.

How it works

Encryption

  1. 1 You enter personal data (name, measurements, etc.)
  2. 2 Your app loads your DEK from the iCloud Keychain
  3. 3 The data is encrypted locally with AES-256-GCM
  4. 4 Only the encrypted blob is sent to our server
  5. 5 These fields never leave your device in plaintext

Decryption

  1. 1 Your app fetches the encrypted blob from the server
  2. 2 On a new device without the Keychain, you unlock the wrapped DEK with your recovery key
  3. 3 Data is decrypted locally on your device
  4. 4 Decrypted data is used in the app, never stored in plaintext remotely

Data deletion

When you delete your account, all data is permanently removed from our database via cascading delete — workouts, measurements, settings, encryption keys. No soft-deletes. Only our hosting provider's automatic backups may still hold data until they are overwritten in their regular rotation.

If you lose your Keychain and your recovery key,
even we cannot recover your encrypted data.

Download reppd