Keeping family photos private: end-to-end encrypted sharing explained

Family photos are some of the most personal data you own: children at bath time, a grandparent in hospital, the house and the car with the number plate showing. Keeping them private isn't about being secretive; it's about deciding who sees them. This article explains what "private" should mean for family photos, what end-to-end encryption adds, and what to check in any app, using the Photohawk app as the example.

Three kinds of privacy

When an app says your photos are private, it can mean very different things:

1. Private from the public. Nobody can find your photos by browsing or searching. Most sharing apps manage this.
2. Private from people you didn't choose. Only the people you shared with can see the photos, and a forwarded link doesn't open them.
3. Private from the service itself. The company running the app can't see your photos either. This is what end-to-end encryption gives you.

Most family sharing is fine at level 1 or 2. Level 3 is the one to look for when photos are very personal or involve children.

What end-to-end encryption means

With ordinary encryption, photos are protected on their way to a service and while stored, but the service holds the keys and can open them.

With end-to-end encryption:

• Each photo is locked on your phone before it leaves.
• Only the people you share with hold the keys to open it, on their own devices.
• The service in the middle passes on and stores locked photos it can't open.

So even if someone got into the service's storage, they'd find photos they couldn't read.

How the Photohawk app protects photos

Photohawk Family, our app for your family's photos, is coming soon to iPhone. Privacy is built in at each step:

• Your photos stay on your phone. Finding faces, people, things and places happens on the phone. Photos leave it only when you share them.
• Sharing is end-to-end encrypted. Each shared photo is locked on your phone with its own key, and only the devices of the people you share with can open it.
• Only the people you share with can see them. No public links to your library, no feed.
• Notifications are decrypted on the phone. When someone shares a photo with you, the notification preview is unlocked on your own phone.
• No ads.

Face data deserves the same care

Organising photos by person means making face data, which privacy laws treat as especially sensitive. In the Photohawk app, face grouping is off until you turn it on; faces are found on your phone; the face data on your phone isn't in your phone backups; and cloud face matching is a separate choice that sends only small face cut-outs, never photos. Turning face grouping off deletes your face data, on your phone and in the cloud. Our article on face grouping and privacy explains it fully.

Children and private sharing

The more personal the photo, the more these choices matter. A few rules many families adopt:

• Share with named adults, never public links.
• No re-posting of photos shared privately.
• Think ten years ahead. Would your child be happy this photo exists?

In the Photohawk app, children are never share recipients. Photos of them can go to the adults you choose, but a child can't be invited or sent photos.

What to check in any photo app

Before trusting an app with family photos, ask:

• Are my photos uploaded to be organised, or is it done on my phone?
• When I share, is it end-to-end encrypted, or can the service open the photos?
• Who can see a shared photo: just the people I chose, or anyone with a link?
• Can I stop sharing with someone, and do new photos stop?
• Are there ads? Is my data used for anything beyond the app?
• How do I delete my data, and my account?

Everyday habits

Technology does part of the job. Habits do the rest:

• Turn off location in photos you post publicly, if you post at all.
• Check backgrounds: house numbers, school logos and car number plates.
• Use a passcode on your phone; it protects your library too.
• Review who you share with now and then.

If you're moving away from posting family photos at all, read family photo sharing without social media, and for sending each person just the photos they're in, see sharing photos with the people in them.

Photohawk Family is coming soon to iPhone, with Android to follow. Keep an eye on photohawk.com for the launch.