How iSIMILAR searches your photos by image

iSIMILAR is a private search engine for similar images in your phone's gallery. You give it a photo and it shows you the ones that look like it. Everything runs on the phone, without internet.

1. One scan, at the start

The first time you open the app, it scans your gallery once, even without a connection. On an iPhone 13 with 15,000 photos it takes 2.5 to 3 minutes; on a Xiaomi Mi A3 (a 2019 mid-range Android phone) with about 8,000 photos, around 4 to 5 minutes. After that, it only processes new photos, and if the scan is interrupted it picks up where it left off. Your originals aren't copied or moved: the app keeps a small visual fingerprint of each photo, on the phone.

2. Search from a photo or the camera

Pick any photo from your gallery, or point the camera at something in front of you: a circuit board, a product on the shelf, a receipt. Results appear in under a second, sorted from most to least similar. You can also sort them by most or least similar, and by newest or oldest.

3. Keep searching from any result

Tap any result to start a new search from it. It's useful when what you're after looks a bit different from your first photo.

4. Act on the results

Open any result to see the photo's details: its date, its size in pixels and its file size. It helps when you're choosing which of several similar photos to keep. Then delete, move to a new or existing album, or share. You always see a preview and confirm before anything happens. Photos you move to an album stop showing up in later searches, so each search shows what's left to sort. On iPhone you can also remove a photo from an album without deleting it, and delete albums from the app. The albums you create from the app have their own viewer: open any photo to see its details or start a new search from it.

5. An optional weekly reminder

If you turn it on, iSIMILAR reminds you once a week to review your new photos.

What it compares

Shape, texture, color and composition. It doesn't recognize objects by name, faces or text. That's why it works best with photos taken in similar conditions: same angle, same light, same background.

Limits you should know

• It finds by category, not by instance: a photo of a circuit board returns circuit boards in general, not one specific client's board.
• It gets it right about 80% of the time.
• Sometimes it mixes up images that look alike but are different things. The best-known case is documents and photos of phone screens, mixed up in about 1 in 5 cases.
• It doesn't learn from your gallery.
• It doesn't search by text, date, location or client.
• It doesn't sync between devices.

Privacy

Your photos and their thumbnails never leave the phone. The visual fingerprints are computed and stored only on the device. The app sends technical data on purchases, usage and errors, never photos or gallery content. Details in the Privacy Policy.