Privacy & Security

Solidarity is built with privacy at its core. Learn how we protect your information.

Your Data Stays Local

On-Device Storage

• All cards stored encrypted on your device
• No cloud storage or central servers
• You control who gets what information

No Tracking

• No analytics or telemetry
• No account creation required
• No data collection by default

Offline-First

• Works without internet connection
• Peer-to-peer sharing doesn’t require servers
• Data never leaves your control

Zero-Knowledge Proofs

What are Zero-Knowledge Proofs?

Zero-knowledge proofs allow you to prove something is true without revealing the underlying information.

How Solidarity Uses ZK Proofs

Prove group membership without revealing identity:

• Verify you work at a company without sharing your name
• Prove attendance at an event without disclosing details
• Confirm membership in an organization anonymously

Benefits:

• Cryptographically secure verification
• No trusted third parties required
• Complete privacy preservation

Granular Privacy Controls

Three Privacy Levels

Public - Anyone can see

• Use for: Large events, public networking
• Contains: Basic professional information

Professional - Verified contacts only

• Use for: Business meetings, client interactions
• Contains: Full work contact details

Personal - Trusted connections

• Use for: Close contacts, personal network
• Contains: Personal phone, private social media

Dynamic Privacy

• Update privacy levels anytime
• Revoke access when needed
• Different information for different contexts

Security Best Practices

For Sharing

1. Start minimal - Share less, add more as trust builds
2. Review regularly - Check what you’ve shared
3. Use appropriate levels - Match privacy to context
4. Verify recipients - Use ZK proofs when available

For Receiving

1. Verify sources - Check group membership when possible
2. Organize contacts - Keep track of where you met people
3. Update information - Remove outdated contacts
4. Respect privacy - Don’t share others’ information

Device Security

1. Enable device encryption - Protect local data
2. Use strong passcode - Secure your device
3. Keep iOS updated - Latest security patches
4. Regular backups - Don’t lose your cards

Privacy FAQ

Q: Can others see my information without my permission?

A: No. You must explicitly share your card for others to see any information.

Q: What happens if I lose my phone?

A: Your cards are encrypted on-device. Without your passcode, they cannot be accessed.

Q: Can Solidarity track who I share with?

A: No. All sharing happens peer-to-peer or via QR codes. We have no visibility into your sharing activity.

Q: How does group verification work?

A: Using zero-knowledge proofs, you can prove membership without revealing your identity. The verification is cryptographic and doesn’t require a central authority.

Q: Can I delete information after sharing?

A: You can stop sharing information, but once someone has received your card, you cannot remotely delete it from their device. Choose your privacy level carefully.

Troubleshooting Privacy Issues

Missing Information

Problem: Received card is missing expected information

Solution:

• Check the privacy level used for sharing
• Ask sender to reshare with appropriate level
• Verify you’re in the right group if applicable

Unwanted Contact

Problem: Someone has your information you don’t want them to have

Solution:

• Review your sharing history
• Adjust privacy levels for future sharing
• Contact the person directly to request removal

Your privacy is your right. Solidarity gives you the tools to protect it.