PrivateMark

What it does

PrivateMark does two things, on-device, no servers, no accounts. 1) Trace any leak. Before you share a photo, PDF, Word or PowerPoint, it weaves in an invisible, per-recipient watermark. If a copy leaks, feed it back and it names whose copy it was. 2) Hidden Photo. Send a picture everyone sees as an innocent cover; your trusted contact opens it in PrivateMark to reveal the real photo, sealed with AES-256.

Welcome, Product Hunt. PrivateMark hides an invisible, per-recipient watermark in every photo and document you share, so a leak names one person, plus send a real photo disguised as an innocent cover. On-device, no accounts. Product Hunt offer: 1 month of Pro free with code PRODUCTHUNT.

You send one private photo to someone you trust. Weeks later it turns up in a WhatsApp group you were never in. Save that copy, drop it into PrivateMark, and it names exactly who you sent it to, from an invisible, per-recipient watermark woven into their copy alone. All on-device . No servers, no accounts. Plus Hidden Photo : send a real picture disguised as an innocent cover only your trusted contact can open. It lives in the pixels, not metadata a screenshot would strip. Tested against the messy realfrom privatemark.app

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