Your address book.
Your rules.

Contastic is an end-to-end encrypted contact sharing platform. Your data stays private — always.

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Why Contastic?

Traditional address books sync your contacts to third-party servers. Contastic keeps you in control.

🔐

End-to-end encrypted

Private contact data is encrypted on your device before it ever leaves. The server only stores encrypted blobs it cannot read.

👥

You decide who sees what

Choose exactly which contact fields to share with each person — phone number with friends, work email with colleagues. Change your mind at any time.

📱

Android + Web

Native Android app syncs contacts to your address book. Web client works in any modern browser.

🔗

Your personal link

Every account gets a short, shareable profile URL like contastic.mundhenk.info/u/ABC1234. Share it anywhere — no app required to view your public details.

Your personal contact card

Every Contastic account comes with a personal profile URL you can share with anyone.

Anyone who visits your link sees the contact fields you've chosen to make public — no account, no app, no friction. Just open the link in a browser and see your card.

Share it in your email signature, on a business card, or as a QR code. When your phone number changes, update it once in Contastic — everyone who subscribes to you gets the new number automatically.

Your profile link contastic.mundhenk.info/u/ABC1234
👤
Jane Smith
📧 jane@example.com
🌐 janesmith.com
📱 Private — subscribers only
🏠 Private — subscribers only

How it works

Simple for users. Zero-knowledge for the server.

1

Create your account

Sign up in seconds. A unique encryption key is created on your device — your private key never leaves it.

2

Add your contact details

Fill in your name, phone, address, or any fields you like. Mark each field as public or private.

3

Share your personal link or QR code

Send your profile URL or let others scan your QR code to view your public details or request access to private ones.

4

Approve and share selectively

Review access requests and choose exactly which private fields to share with each person. Data is encrypted and only they can read it.

Ready to take back your address book?

Try Contastic today — free on web and Android.

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